Delivery of coated hydrophobic active agent particles

ABSTRACT

Embodiments of the invention include devices and coatings for devices including coated hydrophobic active agent particles. In an embodiment, the invention includes a drug delivery device including a substrate; and coated therapeutic agent particles disposed on the substrate, the coated therapeutic agent particles comprising a particulate hydrophobic therapeutic agent; and a cationic agent in contact with the particulate hydrophobic therapeutic agent. Other embodiments are also included herein.

This application is a continuation-in-part application of prior U.S.application Ser. No. 13/469,844, filed May 11, 2012, which claims thebenefit of U.S. Provisional Application No. 61/488,582, filed May 20,2011, the content of all of which is herein incorporated by reference.

FIELD OF THE INVENTION

The present invention relates to devices and coatings for devices suchas medical device. More specifically, the present invention relates todevices and coatings for devices including coated hydrophobic activeagent particles.

BACKGROUND OF THE INVENTION

The vascular system of the human is subject to blockage due to plaquewithin the arteries. Partial and even complete blockage of arteries bythe formation of an atherosclerotic plaque is a well-known and frequentmedical problem. Frequently, such blockage occurs in the coronaryarteries. Blockages may also occur secondary to past treatment ofspecific sites (restenosis—such as that stemming from rapidly dividingsmooth muscle cells). In addition, blockages can also occur in thecontext of peripheral arteries.

Blockages may be treated using atherectomy devices, which mechanicallyremove the plaque; hot or cold lasers, which vaporize the plaque;stents, which hold the artery open; and other devices and proceduresdesigned to increase blood flow through the artery.

One common procedure for the treatment of blocked arteries ispercutaneous transluminal coronary angioplasty (PTCA), also referred toas balloon angioplasty. In this procedure, a catheter having aninflatable balloon at its distal end is introduced into the coronaryartery, the deflated, folded balloon is positioned at the stenotic site,and then the balloon is inflated. Inflation of the balloon disrupts andflattens the plaque against the arterial wall, and stretches thearterial wall, resulting in enlargement of the intraluminal passagewayand increased blood flow. After such expansion, the balloon is deflated,and the balloon catheter removed. A similar procedure, calledpercutaneous transluminal angioplasty (PTA), is used in arteries otherthan coronary arteries in the vascular system. In other relatedprocedures, a small mesh tube, referred to as a stent is implanted atthe stenotic site to help maintain patency of the coronary artery. Inrotoblation procedures, also called percutaneous transluminal rotationalatherectomy (PCRA), a small, diamond-tipped, drill-like device isinserted into the affected artery by a catheterization procedure toremove fatty deposits or plaque. In a cutting balloon procedure, aballoon catheter with small blades is inflated to position the blades,score the plaque and compress the fatty matter into the artery wall.During one or more of these procedures, it may be desirable to deliver atherapeutic agent or drug to the area where the treatment is occurringto prevent restenosis, repair vessel dissections or small aneurysms orprovide other desired therapy.

Additionally, it may be desirable to transfer therapeutic agents toother locations in a mammal, such as the skin, neurovasculature, nasal,oral, the lungs, the mucosa, sinus, the GI tract or the renal peripheralvasculature.

SUMMARY OF THE INVENTION

Embodiments of the invention include devices and coatings for devicesincluding hydrophobic active agent particles coated with cationicagents. In an embodiment, the invention includes a drug delivery deviceincluding a substrate; a hydrophilic polymer layer disposed on thesubstrate; and coated therapeutic agent particles disposed on thehydrophilic polymer layer, the coated therapeutic agent particlescomprising a particulate hydrophobic therapeutic agent; and a cationicagent disposed over the particulate hydrophobic therapeutic agent.

In an embodiment, the invention includes a drug delivery coatingincluding a polymeric layer, the polymeric layer comprising ahydrophilic surface; coated therapeutic agent particles disposed on thehydrophilic surface, the coated therapeutic agent particles comprising aparticulate hydrophobic therapeutic agent core; and a cationic agentsurrounding the particulate hydrophobic therapeutic agent core, thecationic agent exhibiting affinity for the surface of a cell membrane.

In an embodiment, the invention includes a method of forming a drugdelivery coating including applying a hydrophilic base coat onto asubstrate; forming coated therapeutic agent particles, the coatedtherapeutic agent particles comprising a particulate hydrophobictherapeutic agent and a cationic agent disposed over the particulatehydrophobic therapeutic agent core; and applying the coated therapeuticagent particles to the substrate.

This summary is an overview of some of the teachings of the presentapplication and is not intended to be an exclusive or exhaustivetreatment of the present subject matter. Further details are found inthe detailed description and appended claims. Other aspects will beapparent to persons skilled in the art upon reading and understandingthe following detailed description and viewing the drawings that form apart thereof, each of which is not to be taken in a limiting sense. Thescope of the present invention is defined by the appended claims andtheir legal equivalents.

BRIEF DESCRIPTION OF THE FIGURES

The invention may be more completely understood in connection with thefollowing drawings, in which:

FIG. 1 is a schematic cross-sectional diagram of a coating in accordancewith an embodiment herein.

FIG. 2 is a schematic cross-sectional diagram of a coating in accordancewith an embodiment herein.

FIG. 3 is a schematic cross-sectional diagram of a coating in accordancewith an embodiment herein.

FIG. 4 is a schematic cross-sectional diagram of a coating in accordancewith an embodiment herein.

FIG. 5 is a schematic diagram of a device in accordance with anembodiment herein.

While the invention is susceptible to various modifications andalternative forms, specifics thereof have been shown by way of exampleand drawings, and will be described in detail. It should be understood,however, that the invention is not limited to the particular embodimentsdescribed. On the contrary, the intention is to cover modifications,equivalents, and alternatives falling within the spirit and scope of theinvention.

DETAILED DESCRIPTION OF THE INVENTION

The embodiments of the present invention described herein are notintended to be exhaustive or to limit the invention to the precise formsdisclosed in the following detailed description. Rather, the embodimentsare chosen and described so that others skilled in the art canappreciate and understand the principles and practices of the presentinvention.

All publications and patents mentioned herein are hereby incorporated byreference. The publications and patents disclosed herein are providedsolely for their disclosure. Nothing herein is to be construed as anadmission that the inventors are not entitled to antedate anypublication and/or patent, including any publication and/or patent citedherein.

As described above, in association with procedures such as percutaneoustransluminal coronary angioplasty (PTCA), percutaneous transluminalangioplasty (PTA), and the like, it can be desirable to deliver atherapeutic agent or drug to the area where the treatment is occurringto prevent restenosis, repair vessel dissections or small aneurysms orprovide other desired therapy. One approach for accomplishing this is todeliver a therapeutic agent (or active agent) to the desired tissue siteusing a drug delivery device such as a drug eluting balloon catheter ora drug-containing balloon catheter.

Drug delivery coatings for certain medical applications desirablyexhibit various properties. By way of example, in the context of a drugeluting balloon catheter or a drug-containing balloon catheter, thecoating should maintain structural integrity during steps associatedwith preparation of the balloon catheter device include pleating,folding, and curing (such as heat treatment). In addition, it isdesirable for the coating to maintain structural integrity during theprocess of passing through the vasculature through a catheter and/orover the guide wire, with limited loss of the active agent. Yet, it isalso desirable upon inflation of the balloon at the desired site totransfer a substantial amount of the active agent from the balloon andonto the vessel wall. In addition, it is desirable to maximize uptake ofthe active agent into the tissue of the of the vessel wall and reducethe amount of active agent that is washed away into the blood flowingthrough the treatment site in the vasculature.

Embodiments herein can be useful to enhance one or more desirableproperties of drug delivery coatings, such as those properties desirablein the context of drug eluting balloon catheters, drug-containingballoon catheters and similar devices. In various embodiments, a drugdelivery device is provided that includes a substrate and coatedtherapeutic agent particles disposed on the substrate. The coatedtherapeutic agent particles can include a particulate hydrophobictherapeutic agent and a cationic agent disposed over the particulatehydrophobic therapeutic agent.

Referring now to FIG. 1, a schematic cross-sectional diagram (not toscale) is provided of a coating in accordance with an embodiment herein.In this embodiment, coated therapeutic agent particles 104 are disposedon a substrate 102. Exemplary substrates are described in greater detailbelow. The coated therapeutic agent particles 104 can include aplurality of cationic agents 108 disposed over a particulate hydrophobictherapeutic agent 106. It will be appreciated that as actually appliedthere will be many hydrophobic therapeutic agent particulates within agiven coating and that a single particulate is shown in FIG. 1 just forpurposes of ease of illustration. Exemplary cationic agents andhydrophobic therapeutic agents are described in greater detail below.The charge provided by the cationic agents 108 can be electrostaticallyattracted to negative charges and/or polar groups associated with thelipid bilayer 110 of a cell membrane and cellular components within thelipid bilayer 110.

In some embodiments, nucleic acids may also be included in coatingsherein. By way of example, nucleic acids, including but not limited tosiRNA, may be associated with the cationic agent. Exemplary nucleicacids are described in greater detail below. Referring now to FIG. 2, aschematic cross-sectional diagram (not to scale) is provided of anotherembodiment herein. In this embodiment, coated therapeutic agentparticles 204 are disposed on a substrate 202. The coated therapeuticagent particles 204 can include a plurality of cationic agents 208disposed over a particulate hydrophobic therapeutic agent 206. Nucleicacids 212 can be associated with the cationic agent. The charge providedby the cationic agents 208 can be electrostatically attracted tonegative charges and/or polar groups associated with the lipid bilayer210 of a cell membrane and cellular components within the lipid bilayer210.

In some embodiments, an additive may be included along with the coatedtherapeutic agent particles 304 in coatings herein. Referring now toFIG. 3, a schematic cross-sectional diagram (not to scale) is providedof another embodiment. In this embodiment, coated therapeutic agentparticles 304 are disposed on a substrate 302. An additive 314 can bedisposed along with the coated therapeutic agent particles 304. Theamount of the additive 314 can be more than, less than, or equal to theamount of the coated therapeutic agent particles 304. In someembodiments, the additive 314 can form a matrix or layer in which thecoated therapeutic agent particles 304 are disposed. In variousembodiments, the additive can be hydrophilic. Exemplary additivecomponents are described in greater detail below. The coated therapeuticagent particles 304 can include a plurality of cationic agents 308disposed over a particulate hydrophobic therapeutic agent 306. Thecharge provided by the cationic agents 308 can be electrostaticallyattracted to negative charges and/or polar groups associated with thelipid bilayer 310 of a cell membrane and cellular components within thelipid bilayer 310.

In some embodiments, a hydrophilic polymer layer can be disposed on thesurface of the substrate, between the coated therapeutic agent particlesand the surface of the substrate. Exemplary polymers for the hydrophilicpolymer layer are described in greater detail below. Referring now toFIG. 4, a schematic cross-sectional diagram (not to scale) is providedof another embodiment herein. In this embodiment, coated therapeuticagent particles 404 are disposed on a hydrophilic polymer layer 416,which is in turn disposed on a substrate 402. The coated therapeuticagent particles 404 can include a plurality of cationic agents 408disposed over a particulate hydrophobic therapeutic agent 406. Thecharge provided by the cationic agents 408 can be electrostaticallyattracted to negative charges and/or polar groups associated with thelipid bilayer 410 of a cell membrane and cellular components within thelipid bilayer 410.

Referring now to FIG. 5, a schematic view of an exemplary device isshown in accordance with an embodiment. The device 500 can be, forexample, an angioplasty balloon catheter or a drug eluting ballooncatheter or a drug-containing balloon catheter. However, furtherexamples of exemplary devices are described in greater detail below. Thedevice 500 includes a catheter shaft 502 and a manifold end 505. Thedevice 500 also includes an inflatable balloon 504 disposed around thecatheter shaft 502. In FIG. 5, the balloon 504 is shown in an inflatedconfiguration. The catheter shaft 502 can include a channel to conveyfluid through the catheter shaft 502 and to or from the balloon 504, sothat the balloon 504 can selectively go from a deflated configuration tothe inflated configuration and back again.

The manufacture of expandable balloons is well known in the art, and anysuitable process can be carried out to provide the expandable substrateportion of the insertable medical device as described herein. Catheterballoon construction is described in various references, for example,U.S. Pat. Nos. 4,490,421, 5,556,383, 6,210,364, 6,168,748, 6,328,710,and 6,482,348. Molding processes are typically performed for balloonconstruction. In an exemplary molding process, an extruded polymerictube is radially and axially expanded at elevated temperatures within amold having the desired shape of the balloon. The balloon can besubjected to additional treatments following the molding process. Forexample, the formed balloon can be subjected to additional heating stepsto reduce shrinkage of the balloon.

Referring back to FIG. 5, the insertable medical device 500 can alsohave one or more non-expandable (or inelastic) portions. For example, ina balloon catheter, the catheter shaft 502 portion can be thenon-expandable portion. The non-expandable portion can be partially orentirely fabricated from a polymer. Polymers include those formed ofsynthetic polymers, including oligomers, homopolymers, and copolymersresulting from either addition or condensation polymerizations. Examplesof suitable addition polymers include, but are not limited to, acrylicssuch as those polymerized from methyl acrylate, methyl methacrylate,hydroxyethyl methacrylate, hydroxyethyl acrylate, acrylic acid,methacrylic acid, glyceryl acrylate, glyceryl methacrylate,methacrylamide, and acrylamide; vinyls such as ethylene, propylene,vinyl chloride, vinyl acetate, vinyl pyrrolidone, vinylidene difluoride,and styrene. Examples of condensation polymers include, but are notlimited to, polyamides such as polycaprolactam, polylauryl lactam,polyhexamethylene adipamide, and polyhexamethylene dodecanediamide, andalso polyurethanes, polycarbonates, polyamides, polysulfones,poly(ethylene terephthalate), polydimethylsiloxanes, andpolyetherketone. The non-expandable portion can also be partially orentirely fabricated from a metal.

Cationic Agents

Cationic agents used in embodiments herein include compounds containinga portion having a positive charge in aqueous solution at neutral pHalong with a portion that can exhibit affinity for hydrophobic surfaces(such as hydrophobic or amphiphilic properties) and can thereforeinterface with hydrophobic active agents. In some embodiments, cationicagents used in embodiments herein can include those having the generalformula X-Y, wherein X is a radical including a positively charged groupin aqueous solution at neutral pH and Y is a radical exhibitinghydrophobic properties. In some embodiments, the cationic agent caninclude a hydrophilic head and a hydrophobic tail, along with one ormore positively charged groups, typically in the area of the hydrophilichead.

Cationic agents can specifically include cationic lipids and net neutrallipids that have a cationic group. Exemplary lipids can include, but arenot limited to, 3β-[N—(N′,N′-dimethylaminoethane)-carbamoyl]cholesterolhydrochloride (DC-cholesterol); 1,2-dioleoyl-3-trimethylammonium-propane(DOTAP); dimethyldioctadecylammonium (DDAB);1,2-dioleoyl-sn-glycero-3-ethylphosphocholine (EPC);1,2-di-O-octadecenyl-3-trimethylammonium propane (DOTMA);1,2-di-(9Z-octadecenoyl)-3-dimethylammonium-propane (DODAP);1,2-dilinoleyloxy-3-dimethylaminopropane (DLinDMA) and derivativesthereof. Additional lipids can include, but are not limited to,1,2-dioleoyl-sn-glycero-3-phosphoethanolamine (DOPE); cholesterol;1,2-dioctadecanoyl-sn-glycero-3-phosphocholine (DSPC);1,2-distearoyl-sn-glycero-3-phosphoethanolamine (DSPE).

Cationic agents can specifically include cationic polymers. Cationicagents can also include polycation-containing cyclodextrin, histones,protamines, cationized human serum albumin, aminopolysaccharides such aschitosan, peptides such as poly-L-lysine, poly-L-ornithine, andpoly(4-hydroxy-L-proline ester, and polyamines such as polyethylenimine(PEI; available from Sigma Aldrich), polypropylenimine, polyamidoaminedendrimers (PAMAM; available from Sigma Aldrich), cationic polyoxazolineand poly(beta-aminoesters). Cationic agents can also specificallyinclude cationic lipidoids (as described by K. T. Love in thepublication PNAS 107, 1864-1869 (2010)). Other exemplary cationicpolymers include, but are not limited to, block copolymers such asPEG-PEI and PLGA-PEI copolymers.

In other embodiments of the present disclosure, cationic agentscontaining a portion having a positive charge in aqueous solutions atneutral pH include the following Compounds (A-I):

Additionally, other cationic agents include structures of the generalFormula I:

TABLE 1 Formula I

Values for Variables x + z, y and R for Compounds J-R of Formula I.Compound x + z y R Compound J 6 12.5 C₁₂H₂₅ Compound K 1.2 2 C₁₂H₂₅Compound L 6 39 C₁₂H₂₅ Compound M 6 12.5 C₁₄H₂₉ Compound N 1.2 2 C₁₄H₂₉Compound O 6 39 C₁₄H₂₉ Compound P 6 12.5 C₁₆H₃₃ Compound Q 1.2 2 C₁₆H₃₃Compound R 6 39 C₁₆H₃₃

Cationic agents, such as those listed above, can generally be preparedby the reaction of an appropriate hydrophobic epoxide (e.g. oleylepoxide) with a multi-functional amine (e.g. propylene diamine). Detailsof the synthesis of related cationic agents are described by K. T. Lovein the publication PNAS 107, 1864-1869 (2010) and Ghonaim et al., PharmaRes 27, 17-29 (2010).

It will be appreciated that polyamide derivatives of PEI (PEI-amides)can also be applied as cationic agents. PEI-amides can generally beprepared by reacting PEI with an acid or acid derivative such as an acidchloride or an ester to form various PEI-amides. For example, PEI can bereacted with methyl oleate to form PEI-amides.

In yet other embodiments cationic agents can include moieties used tocondense nucleic acids (for example lipids, peptides and other cationicpolymers). In some instances these cationic agents can be used to formlipoplexes and polyplexes.

In some embodiments, the molecular weight of the cationic agent can beabout 1.2 kDa, 2.5 kDa, 10 kDa, 25 kDa, 250 kDa or even, in some cases,750 kDa. In yet other embodiments the molecular weight of the cationicagent can be in the range of 50-100 kDa, 70-100 kDa, 50-250 kDa, 25-100kDa, 2.5-750 kDa or even, in some cases, 2.5-2,000 kDa. Otherembodiments include molecular weights greater than 1.2 kDa, 2.5 kDa, 10kDa, 25 kDa, 250 kDa or even, in some cases, greater than 750 kDa. Otherembodiments can include cationic agents up to 2,000 kDa.

Additive Components

In some embodiments of the present disclosure the additive componentscan be hydrophilic in nature. Exemplary hydrophilic polymers include,but are not limited to, PEG, PVP and PVA.

Exemplary additive components can include saccharides. Saccharides caninclude monosaccharides, disaccharides, trisaccharides,oligosaccharides, and polysaccharides. Polysaccharides can be linear orbranched polysaccharides. Exemplary saccharides can include but are notlimited to dextrose, sucrose, maltose, mannose, trehalose, and the like.Exemplary saccharides can further include, but are not limited to,polysaccharides including pentose, and/or hexose subunits, specificallyincluding glucans such as glycogen and amylopectin, and dextrinsincluding maltodextrins, fructose, mannose, galactose, and the like.Polysaccharides can also include gums such as pullulan, arabinose,galactan, etc.

Saccharides can also include derivatives of polysaccharides. It will beappreciated that polysaccharides include a variety of functional groupsthat can serve as attachment points or can otherwise be chemicallymodified in order to alter characteristics of the saccharide. As justone example, it will be appreciated that saccharide backbones generallyinclude substantial numbers of hydroxyl groups that can be utilized toderivatize the saccharide.

Saccharides can also include copolymers and/or terpolymers, and thelike, that include saccharide and/or saccharide subunits and/or blocks.

Polysaccharides used with embodiments herein can have various molecularweights. By way of example, glycogen used with embodiments herein canhave a molecular weight of greater than about 250,000. In someembodiments glycogen used with embodiments herein can have a molecularweight of between about 100,000 and 10,000,000 Daltons.

Refinement of the molecular weight of polysaccharides can be carried outusing diafiltration. Diafiltration of polysaccharides such asmaltodextrin can be carried out using ultrafiltration membranes withdifferent pore sizes. As an example, use of one or more cassettes withmolecular weight cut-off membranes in the range of about 1K to about 500K can be used in a diafiltration process to provide polysaccharidepreparations with average molecular weights in the range of less than500 kDa, in the range of about 100 kDa to about 500 kDa, in the range ofabout 5 kDa to about 30 kDa, in the range of about 30 kDa to about 100kDa, in the range of about 10 kDa to about 30 kDa, or in the range ofabout 1 kDa to about 10 kDa.

It will be appreciated that polysaccharides such as maltodextrin andamylose of various molecular weights are commercially available from anumber of different sources. For example, Glucidex™ 6 (avg. molecularweight ˜95,000 Da) and Glucidex™ 2 (avg. molecular weight ˜300,000 Da)are available from Roquette (France); and MALTRIN™ maltodextrins ofvarious molecular weights, including molecular weights from about 12,000Da to 15,000 Da are available from GPC (Muscatine, Iowa). Examples ofother hydrophobic polysaccharide derivatives are disclosed in US PatentPublication 2007/0260054 (Chudzik), which is incorporated herein byreference.

Exemplary additive components can include amphiphilic compounds.Amphiphilic compounds include those having a relatively hydrophobicportion and a relatively hydrophilic portion. Exemplary amphiphiliccompounds can include, but are not limited to, polymers including, atleast blocks of, polyvinylpyrrolidone, polyvinyl alcohol, polyethyleneglycol, polyoxazolines (such as poly(2-alkyloxazoline) and derivatives)and the like. Exemplary amphiphilic compounds can specifically includepoloxamers. Poloxamers are nonionic triblock copolymers composed of acentral hydrophobic chain of polyoxypropylene flanked by two hydrophilicchains of polyoxyethylene. Poloxamers are frequently referred to by thetrade name PLURONIC®. It will be appreciated that many aspects of thecopolymer can be varied such the characteristics can be customized. Oneexemplary poloxamer is PLURONIC® F68 (non-ionic, co-polymer of ethyleneand propylene oxide commercially available from BASF Corporation; alsodesignated as F68 and poloxamer F68), which refers to a poloxamer havinga solid form at room temperature, a polyoxypropylene molecular mass ofapproximately 1,800 g/mol and roughly 80% polyoxyethylene content, witha total molecular weight of approximately 8,400 g/mol, the copolymerterminating in primary hydroxyl groups.

Exemplary additive components can further include compounds thatstabilize poorly water soluble pharmaceutical agents. Exemplary additivecomponents providing such stabilization include biocompatible polymers,for example albumins. Additional additive components are described inU.S. Pat. No. 7,034,765 (De et al.), the disclosure of which isincorporated herein by reference. Stabilization of suspensions andemulsions can also be provided by compounds, for example, such assurfactants (e.g. F68).

Hydrophobic Active Agents

It will be appreciated that hydrophobic active agents of embodimentsherein can include agents having many different types of activities.Hydrophobic active agents can specifically include those havingsolubility in water of less than about 100 μg/mL at 25 degrees Celsiusand neutral pH. In various embodiments, hydrophobic active agents canspecifically include those having solubility in water of less than about10 μg/mL at 25 degrees Celsius and neutral pH. In some embodiments,hydrophobic active agents can specifically include those havingsolubility in water of less than about 5 μg/ml at 25 degrees Celsius andneutral pH.

In some exemplary embodiments, active agents can include, but are notlimited to, antiproliferatives such as paclitaxel, sirolimus(rapamycin), zotarolimus, everolimus, temsirolimus, pimecrolimus,tacrolimus, and ridaforolimus; analgesics and anti-inflammatory agentssuch as aloxiprin, auranofin, azapropazone, benorylate, diflunisal,etodolac, fenbufen, fenoprofen calcim, flurbiprofen, ibuprofen,indomethacin, ketoprofen, meclofenamic acid, mefenamic acid, nabumetone,naproxen, oxyphenbutazone, phenylbutazone, piroxicam, sulindac;anti-arrhythmic agents such as amiodarone HCl, disopyramide, flecamideacetate, quinidine sulphate; anti-bacterial agents such as benethaminepenicillin, cinoxacin, ciprofloxacin HCl, clarithromycin, clofazimine,cloxacillin, demeclocycline, doxycycline, erythromycin, ethionamide,imipenem, nalidixic acid, nitrofurantoin, rifampicin, spiramycin,sulphabenzamide, sulphadoxine, sulphamerazine, sulphacetamide,sulphadiazine, sulphafurazole, sulphamethoxazole, sulphapyridine,tetracycline, trimethoprim; anti-coagulants such as dicoumarol,dipyridamole, nicoumalone, phenindione; anti-hypertensive agents such asamlodipine, benidipine, darodipine, dilitazem HCl, diazoxide,felodipine, guanabenz acetate, isradipine, minoxidil, nicardipine HCl,nifedipine, nimodipine, phenoxybenzamine HCl, prazosin HCL, reserpine,terazosin HCL; anti-muscarinic agents: atropine, benzhexyl HCl,biperiden, ethopropazine HCl, hyoscyamine, mepenzolate bromide,oxyphencylcimine HCl, tropicamide; anti-neoplastic agents andimmunosuppressants such as aminoglutethimide, amsacrine, azathioprine,busulphan, chlorambucil, cyclosporin, dacarbazine, estramustine,etoposide, lomustine, melphalan, mercaptopurine, methotrexate,mitomycin, mitotane, mitozantrone, procarbazine HCl, tamoxifen citrate,testolactone; beta-blockers such as acebutolol, alprenolol, atenolol,labetalol, metoprolol, nadolol, oxprenolol, pindolol, propranolol;cardiac inotropic agents such as aminone, digitoxin, digoxin, enoximone,lanatoside C, medigoxin; corticosteroids such as beclomethasone,betamethasone, budesonide, cortisone acetate, desoxymethasone,dexamethasone, fludrocortisone acetate, flunisolide, flucortolone,fluticasone propionate, hydrocortisone, methylprednisolone,prednisolone, prednisone, triamcinolone; lipid regulating agents such asbezafibrate, clofibrate, fenofibrate, gemfibrozil, probucol; nitratesand other anti-anginal agents such as amyl nitrate, glyceryl trinitrate,isosorbide dinitrate, isosorbide mononitrate, pentaerythritoltetranitrate.

Other exemplary embodiments of active agents include, but are notlimited to, active agents for treatment of hypertension (HTN), such asguanethidine.

In a particular embodiment, the hydrophobic active agents are selectedfrom the group consisting of paclitaxel, sirolimus (rapamycin) andmixtures thereof.

In some embodiments, a hydrophobic active agents can be conjugated to acationic agent. The conjugation can include a hydrophobic active agentcovalently bonded to the cationic agent. In some embodiments wherein thehydrophobic agent is conjugated to the cationic agent a linking agentcan be used to attach the hydrophobic agent to the cationic agent.Suitable linking agents include, but are not limited to, polyethyleneglycol, polyethylene oxide and polypeptides of naturally-occurring andnon-naturally occurring amino acids. In some embodiments, linking agentscan be biodegradable or cleavable in vivo to assist in release of thehydrophobic active agents. Exemplary linking agents can further includealkane or aromatic compounds with heteroatom-substitutions such as N, S,Si, Se or O.

In some embodiments, the particulate hydrophobic therapeutic agent canhave an average diameter (“dn”, number average) that is less than about10 μm. Also, in some embodiments, the particulate hydrophobictherapeutic agent can have an average diameter of about 100 nm orlarger. For example, the microparticulates associated with theexpandable elastic portion can have an average diameter in the range ofabout 100 nm to about 10 μm, about 150 nm to about 2 μm, about 200 nm toabout 5 μm, or even about 0.3 μm to about 1 μm.

Nucleic Acids

Nucleic acids used with embodiments of the invention can include varioustypes of nucleic acids that can function to provide a therapeuticeffect. Exemplary types of nucleic acids can include, but are notlimited to, ribonucleic acids (RNA), deoxyribonucleic acids (DNA), smallinterfering RNA (siRNA), micro RNA (miRNA), piwi-interacting RNA(piRNA), short hairpin RNA (shRNA), antisense nucleic acids, aptamers,ribozymes, locked nucleic acids and catalytic DNA. In a particularembodiment, the nucleic acid used is siRNA and/or derivatives thereof.

In some exemplary embodiments of the present disclosure, the range ofthe percent ratio of hydrophobic active agent to cationic agent (e.g. %PTX/% PEI or % PTX/% DOTAP; wt/wt) is from about 99.9/0.1 to about70/30. In yet other embodiments it can be appreciated that the range ofthe percent ratio of hydrophobic active agents is from about 99/1 toabout 73/27; from about 98/2 to about 75/25; from about 98/2 to about86/14; from about 97/3 to about 88/12; from about 95/5 to about 90/10;and even in some exemplary embodiments from about 93/7 to about 91/9.

Hydrophilic Base Coatings

One class of hydrophilic polymers useful as polymeric materials forhydrophilic base coat formation is synthetic hydrophilic polymers.Synthetic hydrophilic polymers that are biostable (i.e., that show noappreciable degradation in vivo) can be prepared from any suitablemonomer including acrylic monomers, vinyl monomers, ether monomers, orcombinations of any one or more of these types of monomers. Acrylicmonomers include, for example, methacrylate, methyl methacrylate,hydroxyethyl methacrylate, hydroxyethyl acrylate, methacrylic acid,acrylic acid, glycerol acrylate, glycerol methacrylate, acrylamide,methacrylamide, dimethylacrylamide (DMA), and derivatives and/ormixtures of any of these. Vinyl monomers include, for example, vinylacetate, vinylpyrrolidone, vinyl alcohol, and derivatives of any ofthese. Ether monomers include, for example, ethylene oxide, propyleneoxide, butylene oxide, and derivatives of any of these. Examples ofpolymers that can be formed from these monomers includepoly(acrylamide), poly(methacrylamide), poly(vinylpyrrolidone),poly(acrylic acid), poly(ethylene glycol), poly(vinyl alcohol), andpoly(HEMA). Examples of hydrophilic copolymers include, for example,methyl vinyl ether/maleic anhydride copolymers and vinylpyrrolidone/(meth)acrylamide copolymers. Mixtures of homopolymers and/orcopolymers can be used.

Examples of some acrylamide-based polymers, such aspoly(N,Ndimethylacrylamide-co-aminopropylmethacrylamide) andpoly(acrylamide-co-N,Ndimethylaminopropylmethacrylamide) are describedin example 2 of U.S. Pat. No. 7,807,750 (Taton et al.), the disclosureof which is incorporated herein by reference.

In some embodiments, the hydrophilic polymer is a vinyl pyrrolidonepolymer, or a vinyl pyrrolidone/(meth)acrylamide copolymer such aspoly(vinylpyrrolidone-comethacrylamide). If a PVP copolymer is used, itcan be a copolymer of vinylpyrrolidone and a monomer selected from thegroup of acrylamide monomers. Exemplary acrylamide monomers include(meth)acrylamide and (meth)acrylamide derivatives, such asalkyl(meth)acrylamide, as exemplified by dimethylacrylamide, andaminoalkyl(meth)acrylamide, as exemplified by aminopropylmethacrylamideand dimethylaminopropylmethacrylamide. For example,poly(vinylpyrrolidone-co-N,N dimethylaminopropylmethacrylamide) isdescribed in example 2 of U.S. Pat. No. 7,807,750 (Taton et al.).

In one embodiment, the polymers and copolymers as described arederivatized with one or more photoactivatable group(s). Exemplaryphotoreactive groups that can be pendent from biostable hydrophilicpolymer include aryl ketones, such as acetophenone, benzophenone,anthraquinone, anthrone, quinone, and anthrone-like heterocycles. Thisprovides a hydrophilic polymer having a pendent activatable photogroupthat can be applied to the expandable and collapsible structure, andthen treated with actinic radiation sufficient to activate thephotogroups and cause covalent bonding to a target, such as the materialof the expandable and collapsible structure. Use of photo-hydrophilicpolymers can be used to provide a durable coating of a flexible hydrogelmatrix, with the hydrophilic polymeric materials covalently bonded tothe material of the expandable and collapsible structure.

A hydrophilic polymer having pendent photoreactive groups can be used toprepare the flexible hydrogel coating. Methods of preparing hydrophilicpolymers having photoreactive groups are known in the art. For example,methods for the preparation of photo-PVP are described in U.S. Pat. No.5,414,075, the disclosure of which is incorporated herein by reference.Methods for the preparation of photo-polyacrylamide are described inU.S. Pat. No. 6,007,833, the disclosure of which is incorporated hereinby reference.

In another embodiment, the polymers and copolymers as described arederivatized with one or more polymerizable group(s). Polymers withpendent polymerizable groups are commonly referred to macromers. Thepolymerizable group(s) can be present at the terminal portions (ends) ofthe polymeric strand or can be present along the length of the polymer.In one embodiment polymerizable groups are located randomly along thelength of the polymer.

Optionally, the coating can include a cross-linking agent. Acrosslinking agent can promote the association of polymers in thecoating, or the bonding of polymers to the coated surface. The choice ofa particular crosslinking agent can depend on the ingredients of thecoating composition.

Suitable crosslinking agents include two or more activatable groups,which can react with the polymers in the composition. Suitableactivatable groups include photoreactive groups as described herein,like aryl ketones, such as acetophenone, benzophenone, anthraquinone,anthrone, quinone, and anthrone-like heterocycles. The photoactivatablecross-linking agent can be ionic, and can have good solubility in anaqueous composition. Thus, in some embodiments, at least one ionicphotoactivatable cross-linking agent is used to form the coating. Theionic cross-linking agent can include an acidic group or salt thereof,such as selected from sulfonic acids, carboxylic acids, phosphonicacids, salts thereof, and the like. Exemplary counter ions includealkali, alkaline earths metals, ammonium, protonated amines, and thelike.

Exemplary ionic photoactivatable cross-linking agents include4,5-bis(4-benzoylphenylmethyleneoxy)benzene-1,3-disulfonic acid or salt;2,5-bis(4-benzoylphenylmethyleneoxy)benzene-1,4-disulfonic acid or salt;2,5-bis(4-benzoylmethyleneoxy)benzene-1-sulfonic acid or salt;N,N-bis[2-(4-benzoylbenzyloxy)ethyl]-2-aminoethanesulfonic acid or salt,and the like. See U.S. Pat. Nos. 6,077,698 (Swan et al.), 6,278,018(Swan), 6,603,040 (Swan) and 7,138,541 (Swan) the disclosures of whichare incorporated herein by reference.

Other exemplary ionic photoactivatable cross-linking agents includeethylenebis(4-benzoylbenzyldimethylammonium)dibromide andhexamethylenebis(4-benzoylbenzyldimethylammonium)dibromide and the like.See U.S. Pat. No. 5,714,360 (Swan et al.) the disclosures of which areincorporated herein by reference.

In yet other embodiments, restrained multifunctional reagents withphotoactivable cross-linking groups can be used. In some examples theserestrained multifunctional reagents include tetrakis (4-benzoylbenzylether) of pentaerthyritol and the tetrakis (4-benzoylbenzoate ester) ofpentaerthyritol. See U.S. Pat. Nos. 5,414,075 (Swan et al.) and5,637,460 (Swan et al.) the disclosures of which are incorporated hereinby reference.

Additional cross-linking agents can include those having formulaPhoto¹-LG-Photo², wherein Photo¹ and Photo² independently represent atleast one photoreactive group and LG represents a linking groupcomprising at least one silicon or at least one phosphorus atom, whereinthe degradable linking agent comprises a covalent linkage between atleast one photoreactive group and the linking group, wherein thecovalent linkage between at least one photoreactive group and thelinking group is interrupted by at least one heteroatom. See U.S. Publ.Pat. App. No. 2011/0245367 (Kurdyumov, et al.), the disclosure of whichis incorporated herein by reference. Further cross-linking agents caninclude those having a core molecule with one or more charged groups andone or more photoreactive groups covalently attached to the coremolecule by one or more degradable linkers. See U.S. Publ. Pat. App. No.2011/0144373 (Swan, et al.), the disclosure of which is incorporatedherein by reference.

Natural polymers can also be used to form the hydrophilic base coat.Natural polymers include polysaccharides, for example, polydextrans,carboxymethylcellulose, and hydroxymethylcellulose; glycosaminoglycans,for example, hyaluronic acid; polypeptides, for example, solubleproteins such as collagen, albumin, and avidin; and combinations ofthese natural polymers. Combinations of natural and synthetic polymerscan also be used.

Substrates

The substrate can be formed from any desirable material, or combinationof materials, suitable for use within the body. In some embodiments thesubstrate is formed from compliant and flexible materials, such aselastomers (polymers with elastic properties). Exemplary elastomers canbe formed from various polymers including polyurethanes and polyurethanecopolymers, polyethylene, styrene-butadiene copolymers, polyisoprene,isobutylene-isoprene copolymers (butyl rubber), including halogenatedbutyl rubber, butadiene-styrene-acrylonitrile copolymers, siliconepolymers, fluorosilicone polymers, polycarbonates, polyamides,polyesters, polyvinyl chloride, polyether-polyester copolymers,polyether-polyamide copolymers, and the like. The substrate can be madeof a single elastomeric material, or a combination of materials.

Other materials for the substrate can include those formed of polymers,including oligomers, homopolymers, and copolymers resulting from eitheraddition or condensation polymerizations. Examples of suitable additionpolymers include, but are not limited to, acrylics such as thosepolymerized from methyl acrylate, methyl methacrylate, hydroxyethylmethacrylate, hydroxyethyl acrylate, acrylic acid, methacrylic acid,glyceryl acrylate, glyceryl methacrylate, methacrylamide, andacrylamide; vinyls such as ethylene, propylene, vinyl chloride, vinylacetate, vinyl pyrrolidone, vinylidene difluoride, and styrene. Examplesof condensation polymers include, but are not limited to, nylons such aspolycaprolactam, polylauryl lactam, polyhexamethylene adipamide, andpolyhexamethylene dodecanediamide, and also polyurethanes,polycarbonates, polyamides, polysulfones, poly(ethylene terephthalate),polydimethylsiloxanes, and polyetherketone.

Beyond polymers, and depending on the type of device, the substrate canalso be formed of other materials such as metals (including metal foilsand metal alloys) and ceramics.

Devices

It will be appreciated that embodiments herein include, and can be usedin conjunction with, various types of devices including, but not limitedto, drug delivery devices such as drug eluting balloon catheters,drug-containing balloon catheters, stents, grafts, and the like.

Some embodiments described herein can be used in conjunction withballoon expandable flow diverters, and self-expanding flow diverters.Other embodiments can include uses in contact with angioplasty balloons(for example, but not limited to, percutaneous transluminal coronaryangioplasty and percutaneous transluminal angioplasty). Yet otherembodiments can include uses in conjunction with sinoplasty balloons forENT treatments, urethral balloons and urethral stents for urologicaltreatments.

Other embodiments of the present disclosure can further be used inconjunction with micro-infusion catheter devices. In some embodiments,micro-infusion catheter devices can be used to target active agents tothe renal sympathetic nerves to treat, for example, hypertension.

Embodiments included herein can also be used in conjunction with theapplication of various active agents to the skin (for example, but notlimited to transdermal drug delivery).

Other exemplary medical applications wherein embodiments of the presentdisclosure can be used further encompass treatments for bladder neckstenosis (e.g. subsequent to transurethral resection of the prostrate),laryngotrachial stenosis (e.g. in conjunction with serial endoscopicdilatation to treat subglottic stenosis, treatment of oral cancers andcold sores and bile duct stenosis (e.g. subsequent to pancreatic,hepatocellular of bile duct cancer). By way of further example,embodiments herein can be used in conjunction with drug applicators.Drug applicators can include those for use with various procedures,including surgical procedures, wherein active agents need to be appliedto specific tissue locations. Examples can include, but are not limitedto, drug applicators that can be used in orthopedic surgery in order toapply active agents to specific surfaces of bone, cartilage, ligaments,or other tissue through physical contact of the drug applicator withthose tissues. Drug applicators can include, without limitation,hand-held drug applicators, drug patches, drug stamps, drug applicationdisks, and the like.

In some embodiments, drug applicators can include a surface having ahydrophilic polymer layer disposed thereon and coated therapeutic agentparticles disposed on the hydrophilic polymer layer, the coatedtherapeutic agent particles comprising a particulate hydrophobictherapeutic agent; and a cationic agent disposed over the particulatehydrophobic therapeutic agent.

In use, various embodiments included herein can enable rapid transfer oftherapeutic agents to specific targeted tissues. For example, in someembodiments, a care provider can create physical contact between aportion of a drug delivery device including a therapeutic agent and thetissue being targeted and the therapeutic agent will be rapidlytransferred from the drug delivery device to that tissue. As such,precise control over which tissues the therapeutic agent is provided tocan be achieved.

One beneficial aspect of various of the embodiments herein is that thetherapeutic agent can be transferred from the drug delivery device orcoating to the targeted tissue very rapidly. In some embodimentssubstantial transfer of the therapeutic agent from the drug deliverydevice or coating to the tissue occurs in 30 minutes or less. In someembodiments substantial transfer of the therapeutic agent from the drugdelivery device or coating to the tissue occurs in 15 minutes or less.In some embodiments substantial transfer of the therapeutic agent fromthe drug delivery device or coating to the tissue occurs in 10 minutesor less. In some embodiments substantial transfer of the therapeuticagent from the drug delivery device or coating to the tissue occurs in 5minutes or less. In some embodiments substantial transfer of thetherapeutic agent from the drug delivery device or coating to the tissueoccurs in 2 minutes or less. In some embodiments substantial transfer ofthe therapeutic agent from the drug delivery device or coating to thetissue occurs in 1 minute or less.

Additional Embodiments

As described above, some embodiments can include a hydrophilic base coator layer. In some embodiments, a hydrophilic polymer solution is formedby combining a hydrophilic polymer with one or more solvents. Exemplaryhydrophilic polymers are described in greater detail above. Thehydrophilic polymer solution can then be applied to a suitablesubstrate, such as an expandable balloon disposed on a catheter shaft.Many different techniques can be used to apply the hydrophilic polymersolution to the substrate. By way of example, exemplary techniques caninclude brush coating, drop coating, blade coating, dip coating, spraycoating, micro-dispersion, and the like.

In some embodiments, such as where a photo-polymer is used to form thehydrophilic layer, an actinic radiation application step can beperformed in order to activate latent photoreactive groups on thehydrophilic polymer or on a cross-linker in order to covalently bond thehydrophilic polymer the substrate surface. By way of example, afterapplying the hydrophilic polymer solution to the substrate, the devicecan be subjected to UV exposure at a desirable wavelength for a periodof time.

Next a hydrophobic active agent can be obtained and processed in orderto prepare it for deposition. In some embodiments, processing of thehydrophobic active agent can include steps such as milling of the activeagent. In some embodiments, processing of the hydrophobic active agentcan include steps such as recrystallization of the active agent. In someembodiments, processing of the hydrophobic active agent can includelyophilizing of the active agent.

In various embodiments, the hydrophobic active agent, as a particulate,can be suspended in water. Using the hydrophobic active agent and acationic agent, coated therapeutic agent particles can be formed. By wayof example, a cationic agent, in water or a different solvent, can beadded to the hydrophobic active agent suspension. In variousembodiments, a mixing or agitation step can be performed in order toallow the hydrophobic active agent to interface with the cationic agent.In some embodiments, the cationic agent will surround the particulatehydrophobic active agent.

In some embodiments, a nucleic acid solution can be added to themixture, either before or after addition of the cationic agent and themixing/agitation steps. In some embodiments, an additive component suchas those described above can be added to the mixture. The mixture can beapplied to the substrate of a device, either directly or on top of ahydrophilic base coat. By way of example, exemplary techniques forapplication can include brush coating, drop coating, blade coating, dipcoating, spray coating, micro-dispersion and the like

After application, the composition can be allowed to dry. In the contextof drug eluting balloon catheters or a drug-containing balloon catheter,for example, the balloons can be folded, pleated and sheathed in asheath. In some embodiments, balloons can be placed in an oven for aperiod of time.

In some embodiments of the present disclosure, an active agent that isnot hydrophobic can be modified to be essentially hydrophobic fordisposition on the hydrophilic polymer layer. Exemplary modificationscan include the preparation of prodrugs, whereby the hydrophobicity ofthe active agent can be modified by covalent linkage to a polymer. Otherexemplary prodrugs can include an active agent that is formed in-situ bybond cleavage of the prodrug. Other exemplary modifications can include,but are not limited to, particles (e.g. nanoparticles or microparticles)containing the active agent encapsulated in a hydrophobic polymer. Insome embodiments the hydrophobic polymer can be biodegradable, releasingthe active agent upon delivery to the targeted tissue. Other exemplarymodifications can include, but are not limited to, micelles or otherconstructs of the like with altered hydrophobicity, formed as a resultof the interaction between the active agent and a lipid additive.

The present invention may be better understood with reference to thefollowing examples. These examples are intended to be representative ofspecific embodiments of the invention, and are not intended as limitingthe scope of the invention.

EXAMPLES Example 1 Paclitaxel Preparation and Balloon Coating Procedure

“Jar-Milled Paclitaxel”: Paclitaxel (LC laboratories) was suspended inwater at 65 mg/mL and milled using 5 mm stabilized zirconia 5×5 mmcylindrical beads (Stanford Materials Corp). After milling for 18 hoursthe slurry was removed from the beads and lyophilized.

“Sonicated Paclitaxel”: Paclitaxel crystals were obtained by suspendingpaclitaxel (LC Laboratories) in water at 50 mg/mL. The paclitaxel wasmicronized using a sonic probe for 30 seconds, and leaving the resultingsuspension for three days at room temperature on an orbital shaker witha 1 hour sonication treatment per day in a sonic bath over the course ofthe three days. The mixture was lyophilized.

Unless otherwise indicated the following NYLON balloons were used in allstudies: 20×3.5 mm.

Hydrophilic basecoats (R) were deposited onto the nylon balloonsurfaces. The hydrophilic basecoat solution included 6.25 g/L polyvinylpyrrolidone (PVP) with benzoylbenzoic acid groups; 1.25 g/Lpolyacrylamide; 2.5 g/L PVP (K90); and 0.05 g/L photo-crosslinker; in asolvent solution of 85:15 water/isopropanol. For examples 1-15,crosslinkers were prepared as described in U.S. Pat. No. 6,278,018,Swan. For examples 16-24, cross-linkers were prepared as described in USPatent Application Publication 2012/0046384, Kurdyumov et al. and U.S.Pat. No. 6,278,018, Swan. After coating the basecoat material was driedat room temperature for 15 minutes and then irradiated with UV light for3 minutes.

Typically, for any given formulation, an amount of 3 μg/mm² paclitaxelfor coating on the balloons was attempted (which is 660 μg paclitaxelper balloon). The paclitaxel containing coating mixture was applied ontop of the cured hydrophilic basecoat (R) by means of a positivedisplacement pipette and dried using a hot air-gun.

All balloons were dried over night at room temperature. The balloonswere folded, pleated and sheathed in a nylon sheath. The balloons weresubsequently placed in a 55° C. oven for 1 hour.

Chemicals were obtained from Sigma Aldrich unless stated otherwise.Amounts (μg) of active agent transferred to the tissue and standarddeviations for Examples 2-15 are listed in Table 3. Amounts (μg) ofactive agent transferred to the tissue and standard deviations forExamples 16-24 are listed in Table 9.

Example 2 Formulations with DOTAP and siRNA

Jar milled lyophilized paclitaxel was suspended in water at 67 mg/mL. To100 μL suspension 31 μL DOTAP at 20 mg/mL in ethanol (Avanti PolarLipids) was added and sonicated for 10 minutes in a sonic bath. Then 4.4μL of 1 mM non-coding siRNA, 0.065 mg, was added. Three balloonsreceived a hydrophilic basecoat (R) and a paclitaxel containing topcoataccording to the procedure as described in Example 1. 8 μL of thepaclitaxel containing mixture was used for the topcoat.

To 130 μL of the paclitaxel/DOTAP/siRNA containing mixture 3.7 mgglycogen (available from VWR) was added (74 μL of a 50 mg/mL solution inwater). Four balloons received a hydrophilic basecoat (R) and apaclitaxel containing topcoat with glycogen according to the procedureas described in Example 1. The paclitaxel-containing mixture (8 μL) wasused for the topcoat.

All balloons were dried over night at room temperature. The balloonswere folded, pleated and sheathed in a nylon sheath. The balloons weresubsequently placed in a 55° C. oven for 1 hour.

Release of the paclitaxel from the coating was then assessed accordingto the following procedure. Excised pig coronary arteries (Pel-FreezBiologicals) were prepared and kept at 37° C. Upon removal of thesheaths from the balloons, the balloons were soaked in PBS at 37° C. for30 seconds and then removed from the PBS. Next, the balloon was expandedin the artery tissue at 60-80 psi for 30 seconds at 37° C. and afterdeflation and removal of the balloon, the artery tissue was rinsed withPBS at 37° C. After removal of the balloon from the tissue and rinsing,the tissue was placed in a methanol/0.1% acetic acid solution. Theresulting methanol and acetic acid solution was tested for paclitaxelcontent using HPLC (“Drug Transfer to Tissue”).

Example 3 Formulations with DOTAP and siRNA

Formulation 1—“PAX+DOTAP1x”

Jar milled paclitaxel was suspended in water at 65 mg/mL and treatedwith a sonic probe for 30 seconds. 100 mg of the suspension (6.35 mgpaclitaxel) was weighed out and 32 μL DOTAP 20 mg/mL solution in ethanolwas added. The mixture was sonicated for 10 minutes. The balloonreceived a hydrophilic basecoat (R) and a paclitaxel containing topcoataccording to the procedure as described in Example 1. Thepaclitaxel-containing mixture (10 μL) was used for the topcoat.

Formulation 2—“PAX+DOTAP2x”

Jar milled paclitaxel was suspended in water at 65 mg/mL and treatedwith sonic probe for 30 seconds. 100 mg of the suspension (6.35 mgpaclitaxel) was weighed out and 64 μL DOTAP 20 mg/mL solution in ethanolwas added. The mixture was sonicated for 10 minutes. The balloonreceived a hydrophilic basecoat (R) and a paclitaxel containing topcoataccording to the procedure as described in Example 1. Thepaclitaxel-containing mixture (10 μL) was used for the topcoat.

Formulation 3—“PAX+DOTAP1x+si”

To formulation 1, 60 μg siRNA was added (4.2 μL 1 mM solution). Theballoon received a hydrophilic basecoat (R) and a paclitaxel containingtopcoat according to the procedure as described in Example 1. Thepaclitaxel-containing mixture (10 μL) was used for the topcoat.

Formulation 4—“PAX+DOTAP2x+si”

To formulation 2, 120 μg siRNA was added: 8.4 μL 1 mM solution. Theballoon received a hydrophilic basecoat (R) and a paclitaxel containingtopcoat according to the procedure as described in Example 1. Thepaclitaxel-containing mixture (10 μL) was used for the topcoat.

Formulation 5—“PAX+DOTAP1x+si+F68”

To formulation 3, 4 μL F68 @ 100 mg/mL in water was added (400 μg, ˜6%w/w total formulation). The balloon received a hydrophilic basecoat (R)and a paclitaxel containing topcoat according to the procedure asdescribed in Example 1. The paclitaxel containing mixture (10 μL) wasused for the topcoat.

Formulation 6—“PAX+DOTAP2x+si+F68”

To formulation 4, 4 μL F68 @ 100 mg/mL in water was added (400 μg, ˜6%w/w total formulation). The balloon received a hydrophilic basecoat (R)and a paclitaxel containing topcoat according to the procedure asdescribed in Example 1. The paclitaxel containing mixture (10 μL) wasused for the topcoat.

All balloons were dried over night at room temperature. The balloonswere folded, pleated and sheathed in a nylon sheath. The balloons weresubsequently placed in a 55° C. oven for 1 hour.

Release of the paclitaxel from the coating was then assessed accordingto the procedure as described in example 2.

Example 4 Formulations with DOTAP

Jar-milled paclitaxel (as above) was used. Alternatively, paclitaxel wasmicronized using a Netsch micronizer, and freeze dried.

Paclitaxel Netsch milled particles were suspended at 67 mg/mL in waterand sonicated for 10 minutes.

Paclitaxel jar milled particles were suspended at 67 mg/mL in water andsonicated for 10 minutes.

Formulation 1

100 mg of the suspension of Netsch milled paclitaxel @ 67 mg/mL in DDW(6.28 mg paclitaxel) was weighed out and sonicated until well dispersed.DOTAP 20 mg/mL solution in ethanol (31.4 μL) was added and sonicated insonic bath for 10 minutes. Two balloons each received a hydrophilicbasecoat (R) and a paclitaxel containing topcoat according to theprocedure as described in Example 1. The paclitaxel-containing mixture(14 μL) was used for the topcoat.

Formulation 2

100 mg of the suspension of Netsch milled paclitaxel @ 67 mg/mL in DDW(6.28 mg paclitaxel) was weighed out and sonicated until well dispersed.0.628 mg DOTAP (31.4 μL DOTAP 20 mg/mL in ethanol) was added andsonicated in sonic bath for 10 minutes. Then 0.063 mg siRNA: 4.4 μLsiRNA @ 1 mM, 14.2 mg/ml was added and vortexed well; sonicated for 5minutes. 4 μL F68 at 10 mg/ml in water was added. Two balloons eachreceived a hydrophilic basecoat (R) and a paclitaxel containing topcoataccording to the procedure as described in Example 1. The paclitaxelcontaining mixture (15 μL) was used for the topcoat.

Formulation 3

100 mg of the suspension of jar milled paclitaxel @ 67 mg/mL in DDW(6.28 mg paclitaxel) was weighed out and sonicated until well dispersed.31.4 μL DOTAP 20 mg/mL solution in ethanol was added and sonicated insonic bath for 10 minutes. Two balloons each received a hydrophilicbasecoat (R) and a paclitaxel containing topcoat according to theprocedure as described in Example 1. The paclitaxel-containing mixture(14 μL) was used for the topcoat. Only one balloon was tested.

Formulation 4

200 mg of the suspension of jar milled paclitaxel @ 67 mg/mL in DDW(12.56 mg paclitaxel) was weighed out and sonicated until welldispersed. 2.51 mg DOTAP (126 μL DOTAP 20 mg/mL in ethanol) was addedand sonicated in sonic bath for 10 minutes. Two balloons each received ahydrophilic basecoat (R) and a paclitaxel containing topcoat accordingto the procedure as described in Example 1. The paclitaxel containingmixture (17.5 μL) was used for the topcoat.

Formulation 5

100 mg of the suspension of jar milled paclitaxel @ 67 mg/mL in DDW(6.28 mg paclitaxel) was weighed out and sonicated until well dispersed.0.628 mg DOTAP (31.4 μL DOTAP 20 mg/mL in ethanol) was added andsonicated in sonic bath for 10 minutes. 4 μL F68 at 10 mg/ml in waterwas added (0.6% vs paclitaxel, or total). Two balloons each received ahydrophilic basecoat (R) and a paclitaxel containing topcoat accordingto the procedure as described in Example 1. The paclitaxel containingmixture (15 μL) was used for the topcoat.

Formulation 6

130 μL of formulation 4 was transferred to a new tube and added 4 μL F68at 100 mg/mL in water (0.5%). Two balloons received a hydrophilicbasecoat (R) and a paclitaxel containing topcoat according to theprocedure as described in Example 1. The paclitaxel-containing mixture(17.5 μL) was used for the topcoat.

Formulation 7

200 mg of the suspension of jar milled paclitaxel at 67 mg/mL in DDW(12.56 mg paclitaxel) was weighed out and sonicated until welldispersed. 1.26 mg DOTAP: 63 μL DOTAP 20 mg/mL in ethanol was added andsonicated in sonic bath for 10 minutes. Then 0.126 mg siRNA: 8.8 μLsiRNA at 1 mM, 14.2 mg/ml was added and vortexed well; sonicated for 5minutes. 8 μL F68 at 10 mg/ml in water was added. Two balloons eachreceived a hydrophilic basecoat (R) and a paclitaxel containing topcoataccording to the procedure as described in Example 1. of the paclitaxelcontaining mixture (15 μL) was used for the topcoat.

All balloons were dried over night at room temperature. The balloonswere folded, pleated and sheathed in a nylon sheath. The balloons weresubsequently placed in a 55° C. oven for 1 hour. Release of thepaclitaxel from the coating was then assessed according to the procedureas described in example 2.

Example 5 Coating Transfer from Rods

The top surface of 5 cm long rods having a 5 mm diameter were coatedwith the hydrophilic base coat (R) as described above. The coating wasapplied by brushing the surfaces of the rods with the solution, dryingfor 15 minutes at room temperature and subsequently irradiating for 3minutes with UV. Three formulations were prepared:

Formulation 1

Jar-milled paclitaxel was suspended in water at 67 mg/mL. 100 mg of thesuspension (6.28 mg paclitaxel) was weighed out and sonicated until welldispersed. 1.26 mg DOTAP (62.8 μL DOTAP 20 mg/mL in ethanol) was addedand sonicated in sonic bath for 10 minutes.

Formulation 2

Jar-milled paclitaxel was suspended in water at 67 mg/mL. 100 mg of thesuspension (6.28 mg paclitaxel) was weighed out and sonicated until welldispersed. 1.26 mg DOTAP (62.8 μL DOTAP 20 mg/mL in ethanol) was addedand sonicated in sonic bath for 10 minutes. Then F68 was added 5% w/wtotal formulation as a 100 mg/mL solution in water

Formulation 3

Jar-milled paclitaxel was suspended in water at 67 mg/mL. 100 mg of thesuspension (6.28 mg paclitaxel) was weighed out and sonicated until welldispersed. 1.26 mg DOTAP (62.8 μL DOTAP 20 mg/mL in ethanol) was addedand sonicated in sonic bath for 10 minutes. Then 62.8 μL dextran (100mg/mL in water) was added.

In triplicate, the rods received the paclitaxel containing topcoat bypipetting 5 μL of one of the formulations and letting dry at roomtemperature overnight.

Ex vivo pig skin tissue was trimmed from fat and excised with a 8 mmtissue excision tool (Sklar) and kept at 37° C. The rods were soaked for30 seconds in PBS at 37° C. Subsequently the rods were impressed intothe excised tissue for 30 seconds. The tissue samples were placed in amethanol/0.1% acetic acid solution in a vial with tissue disruptionmedia. The tissue was disrupted to extract transferred paclitaxel

Example 6 Varying Ratios of Components

10 NYLON balloon stubs received a hydrophilic basecoat (R) according tothe procedure as described in Example 1.

Jar-milled paclitaxel was suspended in water at 65 mg/mL. DOTAPdissolved in ethanol at 25 mg/mL was added to the formulation at 20 or40% w/w paclitaxel and sonicated in sonic bath for 10 minutes. To someof the resulting mixtures gelatine B, glycogen or dextran was added as a100 mg/mL solution in water at 33% or 50% w/w total matrix. Theformulations were applied as a topcoat on the balloon (following theprocedure in Example 1), aiming for approximately for a total of 700 μgpaclitaxel in the coating. The balloons were folded, pleated andsheathed in a nylon sheath. The balloons were subsequently placed in a55° C. oven for 1 hour.

Release of the paclitaxel from the coating was then assessed accordingto the procedure as described in example 2.

Example 7 Formulations with PLURONIC® F68

Formulations were prepared by suspending jar-milled paclitaxel in waterat 65 mg/mL. DOTAP dissolved in ethanol at 25 mg/mL was added to theformulation at 20% w/w paclitaxel. To the resulting mixtures PLURONIC®F68 (BASF Corporation) was added as a 10 or 100 mg/mL solution in water,reaching 0.6-5% w/w of the total matrix. The formulations weretop-coated on balloons with hydrophilic base-coats R as described inexperiment 1.

All balloons were dried over night at room temperature. The balloonswere folded, pleated and sheathed in a nylon sheath. The balloons weresubsequently placed in a 55° C. oven for 1 hour.

Release of the paclitaxel from the coating was then assessed accordingto the procedure as described in example 2.

Example 8 Amorphous Paclitaxel Nanoparticles with DOTAP orPolyethyleneimine

(i) Preparation of Amorphous Paclitaxel Particles:

In triplicate, an average of 6.2 mg of paclitaxel was dissolved in 50 μLchloroform. The solution was dispersed in 1 mL BSA at 50 mg/mL in waterusing a sonic probe for 20 seconds. The obtained emulsions were spun ina centrifuge for 15 minutes at 5000 rpm. The clear supernatant wasaspirated; the residue was frozen and lyophilized. The residues weighedon average 9.8 mg. To remove the remaining BSA, the solids weredispersed in 1 mL of fresh water using a sonic bath and subsequentlyspun for 10 minutes at 10,000 rpm. The supernatant was aspirated.

(ii) Preparation of DOTAP Dispersion in Water:

5 mL of a DOTAP solution at 25 mg/mL in ethanol was placed in a glassround-bottom container and evaporated under vacuum to obtain a film. TheDOTAP was dispersed in 12.5 mL water by adding batches of 4.2 mL waterto the glass container and briefly sonication in a sonic bath. Thebatches were combined, sonicated for 10 minutes in a sonic bath andfiltered through a 0.45 μm filter.

Balloons were base- and top-coated following the procedure described inExample 1. In order to obtain the formulations for the paclitaxelcontaining topcoats, DOTAP dispersed in water or an aqueous solution ofPEI was added to the obtained amorphous paclitaxel particles as follows:

-   -   1. 114 μL of a DOTAP dispersion in water at 10 mg/mL was added        to 5.7 μg paclitaxel. 15 μL was used to coat balloon material,    -   2. 62 μL polyethyleneimine low molecular weight (PEI-LMW) at 20        mg/mL with 31 μL water was added to 6.2 μg paclitaxel. 10 μL was        used to coat balloon material,    -   3. 67 μL polyethyleneimine 750 kDa (PEI-HMW) at 20 mg/mL with 33        μL water was added to 6.7 μg paclitaxel. 10 μL was used to coat        balloon material.

All balloons were dried over night at room temperature. The balloonswere folded, pleated and sheathed in a nylon sheath. The balloons weresubsequently placed in a 55° C. oven for 1 hour.

Release of the paclitaxel from the coating was then assessed accordingto the procedure as described in example 2.

Example 9 Z-Potential Measurements

Paclitaxel (5 mg) was dissolved in 10 μL benzyl alcohol. The solutionwas dispersed in 1 mL BSA at 50 mg/mL in water using a sonic probe for20 seconds. The obtained emulsion was divided into 5 times 200 μLportions which were spun in a centrifuge for 10 minutes at 10000 rpm(residuals A-E). The clear supernatant was aspirated.

A. The residue was resuspended in 1 mL of DDW. This mixture was diluted10 times.

B. 10 μL of a chitosan solution 10 mg/mL in 1% acetic acid was addedwith 10 μL DDW. The resulting suspension was diluted in DDW 10 times.

C. 1 mL of a protamine solution 1 mg/mL in DDW was added. The resultingsuspension was diluted in DDW 10 times.

D. The solids were dispersed in 500 μL of DDW using a sonic bath andsubsequently spun for 10 minutes at 10,000 rpm. The supernatant wasaspirated. 5 mL of a DOTAP solution at 25 mg/mL in ethanol was placed ina glass round-bottom container and evaporated under vacuum to obtain afilm. The DOTAP was dispersed in 12.5 mL water by adding batches of 4.2mL water to the glass container and briefly sonication in a sonic bath.The batches were combined, sonicated for 10 minutes in a sonic bath andfiltered through a 0.45 μm filter. To the amorphous paclitaxel residue25 μL of a DOTAP dispersion in water at 10 mg/mL was added and sonicatedin sonic bath. The resulting dispersion was diluted in DDW 10 times.

Z-sizing measurements were taken using a Z-sizer (available fromMalvern) showing the formation of negatively charged droplets upondispersion of dissolved PTX in a BSA solution. Positively chargedparticles were obtained upon addition of chitosan, protamine or DOTAPsolutions.

TABLE 2 Temperature (° C.) and ZP values (mV) for Example 9. Sample NameT (° C.) ZP (mV) PTX/BSA in Water 25 −23.1 Chitosan 25 +63.8 DOTAP 25+58 Protamine 37 +12.3

Example 10 F68 on PTX/DOTAP Formulation

Formulations were prepared by suspending jar-milled paclitaxel in waterat 65 mg/mL. DOTAP dissolved in ethanol at 25 mg/mL was added to theformulation at 20% w/w paclitaxel. To the resulting mixtures F68 wasadded 2-16 μL at 100 mg/mL solution in water, reaching 5-34% w/w of thetotal matrix (50% w/w PTX). The balloon stubs were base- and top-coatedfollowing the procedure described in example 1. Additionally a PTX/DOTAP80:20% w/w formulation was tested. The formulations were top-coated onballoon stubs with hydrophilic base-coat F (n=2 per formulation).

The balloons were folded, pleated and sheathed in a nylon sheath. Theballoons were subsequently placed in a 55° C. oven for 1 hour.

Release of the paclitaxel from the coating was then assessed accordingto the procedure as described in example 2.

Example 11 Use of Amorphous PTX and Different Cationic Moieties

Four balloons were base- and top-coated following the proceduredescribed in experiment 1. The following formulations were top-coated onballoon-stubs with hydrophilic base-coat R. (n=1 per formulation).

In each of 4 tubes 5-7 mg of paclitaxel was dissolved in 50 μLchloroform. The solution was dispersed in 1 mL BSA at 50 mg/mL in waterusing a sonic probe for 20 seconds. The obtained emulsions were spun ina centrifuge for 10 minutes at 5000 rpm. The clear supernatant wasaspirated and the residue was frozen on dry ice and subsequentlylyophilized. (“paclitaxel residue”).

A. Started with 4.8 μg paclitaxel. Paclitaxel residue was reconstitutedin 96 μL DDW. 14 μL was used to coat balloon material.

B. Started with 7.1 μg paclitaxel. Residual BSA was removed bydispersing the solids in 1 mL of fresh water using a sonic bath andsubsequently spun for 10 minutes at 10,000 rpm. The supernatant wasaspirated. 5 mL of a DOTAP solution at 25 mg/mL in ethanol was placed ina glass round-bottom container and evaporated under vacuum to obtain afilm. The DOTAP was dispersed in 12.5 mL water by adding batches of 4.2mL water to the glass container and briefly sonication in a sonic bath.The batches were combined, sonicated for 10 minutes in a sonic bath andfiltered through a 0.45 μm filter. 142 μL of the DOTAP dispersion inwater at 10 mg/mL was added to the paclitaxel residue. 14 μL was used tocoat balloon material.

C. Started with 7.1 μg paclitaxel. Chitosan was dissolved in 1% aceticacid at 100 mg/mL and 57 μL was added to the paclitaxel residue. Then 57μL DDW was added. Particles were dispersed using a sonic bath. Theballoon was coated with 14 μL of this material.

D. Started with 5.1 μg paclitaxel. Protamine was dissolved in DDW at 10mg/mL. 51 μL of the protamine solution was added with additional 51 μLDDW to the paclitaxel residue. Particles were dispersed using a sonicbath. The balloon was coated with 14 μL of this material.

The balloons were folded, pleated and sheathed in a nylon sheath. Theballoons were subsequently placed in a 55° C. oven for 1 hour.

Release of the paclitaxel from the coating was then assessed accordingto the procedure as described in example 2

Example 12 Study IV Flow Experiment

Full length balloon catheters received hydrophilic base coats asdescribed in experiment 1. Paclitaxel containing formulations werecoated on full length catheter balloons and tested in ex-vivo pigcoronary arteries in the flow experiment.

1.) Flow systems: Two open flow loops of PBS in the system were used.One, circulating at 70 mL/min, 2 L total and at 37° C. was for theartery in which the balloon is tested. The other, at 280 mL/min, 1 Ltotal and at 37° C., was for a manifold that supported four arteries atonce (flow at the output was thus 70 mL/min).

2.) Artery connections: Pig coronary arteries for testing were preparedby trimming and gluing (with a cyanoacrylate gel glue (“super glue”))onto a 200 μL pipette tip. The tip was trimmed on the short end suchthat the opening in the tip was ˜2-3 mm in diameter. After gluing,arteries were trimmed to be 30 mm from the end of the pipette tip to thefree end of the artery. Arteries were held in PBS at room temperatureprior to testing.

Each piece of tubing terminated in a 1-mL pipette tip that served as ameans to affix arteries. At the test site, the tip was trimmed to fitinto the tubing at the large end and to be larger than the diameter ofthe 7F guide catheter at the small end. In the manifold, the tips weretrimmed to fit snugly on the Y-connectors on the large end but were nottrimmed on the small end. The resistance provided by the small tiporifice ensured equal flow through the four ports.

For testing, arteries were put onto the end of the flow tubing bypress-fitting the smaller yellow pipette tip onto the larger blue tip.

10 mL PBS was drawn into the syringe (on hemostat Y connector) andflushed through the guide catheter to ensure the catheter was filledwith PBS. The prepared pig coronary artery was placed on the test loopby pressing it onto the pipette end. Then coated balloon catheter wasintroduced as the hemostat was opened wide. The catheter was pushed tothe point where the guide exited the catheter and the guidewire wasremoved. The hemostat was closed somewhat to reduce backflow. Then theballoon catheter was pushed to the treatment site inside the preparedcoronary artery and the hemostat was closed tightly. The balloon wasinflated to 6 ATM and held for 30 seconds. The hemostat was opened andthe balloon catheter was deflated and removed. The artery was thenremoved from test loop and placed on second flow manifold (one of fourspaces) and left for on flow manifold for 13 minutes, counted from timeof deflation of the balloon. The artery was cut from pipette tip placedin a methanol/0.1% acetic acid solution. The resulting methanol andacetic acid solution was tested for paclitaxel content using HPLC (“DrugTransfer to Tissue”).

Example 13 Release of Paclitaxel from Full Length Balloon Catheters

One full length balloon catheter and 2 balloon stubs received ahydrophilic basecoat (R) according to example 1 and were coated with thefollowing formulations:

A) Jar-milled paclitaxel was suspended in water at 67 mg/mL. 100 mg ofthe suspension (6.28 mg paclitaxel) was weighed out and sonicated untilwell dispersed. 1.26 mg DOTAP (62.8 μL DOTAP 20 mg/mL in ethanol) wasadded and sonicated in sonic bath for 10 minutes. Then 62.8 μL dextran(100 mg/mL in water) was added. The balloon was coated with 22.5 μL ofthis material.

B) Jar-milled paclitaxel was suspended in water at 67 mg/mL. 100 mg ofthe suspension (6.28 mg paclitaxel) was weighed out and sonicated untilwell dispersed. 1.26 mg DOTAP (62.8 μL DOTAP 20 mg/mL in ethanol) wasadded and sonicated in sonic bath for 10 minutes. Then 62.8 μL glycogen(100 mg/mL in water) was added. The balloon was coated with 22.5 μL ofthis material.

C) Jar-milled paclitaxel was suspended in water at 67 mg/mL. 100 mg ofthe suspension (6.28 mg paclitaxel) was weighed out and sonicated untilwell dispersed. 1.26 mg DOTAP (62.8 μL DOTAP 20 mg/mL in ethanol) wasadded and sonicated in sonic bath for 10 minutes. A solution of gelatintype A (100 mg/mL in water) was warmed to 37° C. Then 62.8 μL was addedto the mixture. The balloon was coated with 22.5 μL of this material.

D) Jar-milled paclitaxel was suspended in water at 67 mg/mL. Thesuspension (100 mg; 6.28 mg paclitaxel) was weighed out and sonicateduntil well dispersed. A mixture of 953 μg DOTAP and 318 μg cholesterolin 51 μL ethanol was added and sonicated in sonic bath for 10 minutes.The balloon was coated with 15.5 μL of this material.

The topcoats were dried under hot air and left further to dry over nightat room temperature. The balloons were then folded, pleated and sheathedin a nylon sheath. The balloons were subsequently placed in a 55° C.oven for 1 hour.

The full length catheter was tested according to the procedure inexample 12.

Release of the paclitaxel from the coating on the two balloon stubs wasassessed according to the procedure as described in example 2.

Example 14 Release of Paclitaxel from Balloons

Three full-length balloon catheters per formulation received ahydrophilic basecoat (R) according to example 1 and were top-coated withthe following formulations:

A) Jar-milled paclitaxel was suspended in water at 67 mg/mL. 100 mg ofthe suspension (6.28 mg paclitaxel) was weighed out and sonicated untilwell dispersed. 1.26 mg DOTAP (62.8 μL DOTAP 20 mg/mL in ethanol) wasadded and sonicated in sonic bath for 10 minutes. Then 62.8 μL dextran(100 mg/mL in water) was added. The balloon was coated with 22.5 μL ofthis material.

B) Jar-milled paclitaxel was suspended in water at 67 mg/mL. 100 mg ofthe suspension (6.28 mg paclitaxel) was weighed out and sonicated untilwell dispersed. 1.26 mg DOTAP (62.8 μL DOTAP 20 mg/mL in ethanol) wasadded and sonicated in sonic bath for 10 minutes. Then 62.8 μL glycogen(100 mg/mL in water) was added. The balloon was coated with 22.5 μL ofthis material.

C) Jar-milled paclitaxel was suspended in water at 67 mg/mL. 100 mg ofthe suspension (6.28 mg paclitaxel) was weighed out and sonicated untilwell dispersed. 1.26 mg DOTAP (62.8 μL DOTAP 20 mg/mL in ethanol) wasadded and sonicated in sonic bath for 10 minutes. To the resultingmixture PLURONIC® F68 (available from BASF Corporation) was added as a100 mg/mL solution in water, reaching 5% w/w of the total coatingformulation.

The topcoats were dried under hot air and left further to dry over nightat room temperature. The balloons were then folded, pleated and sheathedin a nylon sheath. The balloons were subsequently placed in a 55° C.oven for 1 hour.

The full length catheters were tested according to the procedure inexample 12.

Example 15 Release of Paclitaxel from Balloons

Three full-length balloon catheters per formulation received thehydrophilic basecoat (R) according to example 1 and were top-coated withthe following formulations:

Per formulation, 5-6 mg of paclitaxel was dissolved in 50 μL chloroform.The solution was dispersed in 1 mL BSA at 50 mg/mL in water using asonic probe for 20 seconds. The obtained emulsions were spun in acentrifuge for 15 minutes at 5000 rpm. The clear supernatant wasaspirated; the residue was frozen and lyophilized. The residues weighedon average 9.8 mg. To remove the remaining BSA, the solids weredispersed in 1 mL of fresh water using a sonic bath and subsequentlyspun for 10 minutes at 10,000 rpm. The supernatant was aspirated(“paclitaxel residue”).

5 mL of a DOTAP solution at 25 mg/mL in ethanol was placed in a glassround-bottom container and evaporated under vacuum to obtain a film. TheDOTAP was dispersed in 12.5 mL water by adding batches of 4.2 mL waterto the glass container and briefly sonication in a sonic bath. Thebatches were combined, sonicated for 10 minutes in a sonic bath andfiltered through a 0.45 μm filter.

Polyethyleneimine at high molecular weight 50% w/w in water (Sigma) wasdiluted in DDW to a 2% w/w or 20 mg/mL solution.

To the amorphous paclitaxel residues DOTAP or PEI in water was added asfollows:

1. (5 μg paclitaxel) 100 μL of a DOTAP dispersion in water at 10 mg/mLwas added to the paclitaxel residue. 15.8 μL was used to coat balloonmaterial.

2. (6 μg paclitaxel) 60 μL polyethyleneimine high molecular weight(PEI-HMW) at 20 mg/mL was added with 30 μL water. 11.8 μL was used tocoat balloon material.

3. (5 μg paclitaxel) 100 μL of a DOTAP dispersion in water at 10 mg/mLwas added to the paclitaxel residue. Then 50 μL dextran (100 mg/mL inwater) was added. The balloon was coated with 23.8 μL of this material.

4. 5 mg jar-milled paclitaxel was suspended in 75 μL water and sonicateduntil well dispersed. 1 mg DOTAP (40 μL DOTAP 25 mg/mL in ethanol) wasadded and sonicated in sonic bath for 10 minutes. 18.2 μL was used tocoat balloon material.

The topcoats were dried under hot air and left further to dry over nightat room temperature. The balloons were then folded, pleated and sheathedin a nylon sheath. The balloons were subsequently placed in a 55° C.oven for 1 hour.

The full length catheters were tested according to the procedure inexample 12.

TABLE 3 Tissue Transfer (μg) and Standard Deviations for Examples 2-15.Active Agent Tissue transfer Standard Example Description (μg) DeviationExample 2 PTX/DOTAP/siRNA 42.05 15.09 PTX/DOTAP/siRNA/glycogen 71.2913.71 Example 3 PTX + DOTAP 10% w/w 88.44 PTX + DOTAP 20% w/w 102.68PTX + DOTAP 10% w/w + siRNA 116.92 PTX + DOTAP 20% w/w + siRNA 107.64PTX + DOTAP 10% w/w + siRNA + 152.2 F68 PTX + DOTAP 20% w/w + siRNA +109.8 F68 Example 4 PTX (Netsch milled)/DOTAP 10:1 w/w 112.70 40.76(formulation 1) PTX (Netsch milled)/ 112.50 6.70 DOTAP/F68/siRNA10:1:0.5:0.1 w/w (formulation 2) PTX (Jar milled)/DOTAP 10:1 w/w 82.40(formulation 3) PTX (Jar milled)/DOTAP 5:1 w/w 154.82 80.47 (formulation4) PTX (Jar milled)/DOTAP/F68 10:1:0.5 w/w 157.80 10.13 (formulation 5)PTX (Jar milled)/DOTAP/F68 5:1:0.5 w/w 178.94 0.08 (formulation 6) PTX(Jar milled)/DOTAP/F68/siRNA 122.64 8.26 5:1:0.5:0.1 w/w (formulation 7)Example 5 PTX/DOTAP 5:1 107.21 18.76 PTX/DOTAP/F68 5:1:0.16 99.06 12.44PTX/DOTAP/Dext 5:1:5 116.21 3.34 Example 6 PTX/DOTAP 15:6 w/w 107.8PTX/DOTAP/Gelatine B 15:3:5 w/w 80.12 PTX/DOTAP/Gelatine B 15:6:5 w/w78.4 PTX/DOTAP/Gelatine B 15:3:5 w/w 79.2 PTX/DOTAP/Glycogen 15:3:15 w/w293.32 PTX/DOTAP/Glycogen 15:3:5 w/w 116.32 PTX/DOTAP/Glycogen 15:6:5w/w 80.88 PTX/DOTAP/Dextran 15:3:5 w/w 128.76 PTX/DOTAP/Dextran 15:6:5w/w 125.92 PTX/DOTAP/Dextran 15:3:15 w/w 172.16 Example 7 PTX/DOTAP/F685:1:0.32 w/w 180.30 91.22 PTX/DOTAP/F68 5:1:0.16 w/w 148.46 41.83PTX/DOTAP/F68 5:1:0.04 w/w 91.62 9.64 Example 8 PTX (amorphous)/DOTAP5:1 w/w 185.76 73.19 PTX (amorphous)/PEI-LMW 5:1 w/w 69.96 30.79 PTX(amorphous)/PEI-HMW 5:1 w/w 260.63 168.15 Example 10 PTX/DOTAP 5:1 139.86.2 PTX/DOTAP/F68 5:1:0.32 w/w 151.7 48.8 PTX/DOTAP/F68 5:1:0.65 w/w80.8 12.6 PTX/DOTAP/F68 5:1:1.3 w/w 69.9 4.9 PTX/DOTAP/F68 5:1:2.6 w/w86.7 17.1 Example 11 PTX only 62.08 PTX/DOTAP 5:1 w/w 282.36PTX/chitosan 10:1 w/w 48.32 PTX/Protamine 10:1 w/w 60.68 Example 13PTX/DOTAP/DEXTRAN static test 116.94 5.23 PTX/DOTAP/DEXTRAN flow test75.84 PTX/DOTAP/gelatine A static test 69.18 28.60 PTX/DOTAP/gelatine Aflow test 7.20 PTX/DOTAP/glycogen static test 118.00 38.41PTX/DOTAP/glycogen flow test 60.24 PTX/DOTAP/Cholesterol static test103.98 3.87 PTX/DOTAP/Cholesterol flow test 40.64 Example 14PTX/DOTAP/F68 79:16:5 w/w 68.97 29.08 PTX/DOTAP/glycogen 45.5:9:45.5 w/w72.57 19.14 PTX/DOTAP/dextran 45.5:9:45.5 w/w 83.28 38.72 Example 15 83%PTX (amorphous)/17% DOTAP 35.89 7.50 w/w 83% PTX (amorphous)/17% PEI-65.94 12.57 HMW w/w 45.5% PTX (amorphous)/9% DOTAP/ 75.67 14.09 45.5%dextran w/w 83% PTX (jar milled)/17% DOTAP 49.12 13.83 w/w

Example 16 PEI and PAMAM Dendrimers

Twelve balloon stubs were coated with the hydrophilic base coat (R) asdescribed in Example 1. The following formulations were applied on topof the basecoat:

Stub #1 and #2: coating was applied from a 25% ethanol/75% methanolsolution containing 75 mg/mL paclitaxel and 6.25 mg/mL polyethyleneimine(PEI-HMW) of 750 kDa. Total drug was targeted at 660 μg.

Stub #3 and #4: coating was applied from a 25% ethanol/75% methanolsolution containing 75 mg/mL paclitaxel and 6.25 mg/mL polyamidoaminedendrimer (PAMAM, Gen. 4). Total drug was targeted at 660 μg.

Stub #5, #6 and #7: Paclitaxel was dissolved in chloroform at 100 mg/mL.400 μL of this solution was emulsified in 10 mL aqueous BSA solution at50 mg/mL using a sonic probe for 60 seconds. The resulting emulsion waslyophilized. BSA was removed from the amorphous paclitaxel by washingthe solids three times with double distilled water. To 6.5 mg amorphouspaclitaxel 33 μL water and 65 μL aqueous solution of PEI-HMW 20 mg/mLwas added. The coating solution was vortexed and sonicated on sonicbath. Coating the tubs total drug was targeted at 660 μg.

Stub #8, #9 and #10: To a mixture of 7 mg jar-milled paclitaxel in 70 μLwater was added 70 μL of an aqueous solution of PEI-HMW at 20 mg/mL.Total drug was targeted at 660 μg.

Stub #11 and #12: Mixture of jar-milled paclitaxel at 50 mg/mL in DDWwith 10 mg/mL PAMAM in ethanol. PAMAM was added to the paclitaxelsuspension until reaching a wt/wt ratio of 17:83 PAMAM versuspaclitaxel. Total drug was targeted at 660 μg.

The topcoats were dried under hot air and left further to dry over nightat room temperature. The balloons were then folded, pleated and sheathedin a nylon sheath. The balloons were subsequently placed in a 55° C.oven for 1 hour.

Release of the paclitaxel from the coating was then assessed accordingto the procedure as described in example 2.

Example 17 Release of Paclitaxel from Full Length Balloon Catheters

Nine full-length balloon catheters received a hydrophilic basecoat (R)according to example 1 and were top-coated with the followingformulations (n=3 per formulation):

-   -   1. 19 mg Jar-milled paclitaxel was combined with 283.6 μL        distilled water and twice sonicated using a sonic probe for 20        seconds at power setting “3”. 99.5 mg of the mixture was weighed        out and added 62.9 μL of a solution of PEI 750 kDa 20 mg/mL in        distilled water. Three catheters each were top-coated with 20.5        μL of the formulation.    -   2. 103.4 mg of the paclitaxel in water suspension was weighed        out. 65.4 μL of a 20 mg/mL PEI 750 kDa in water solution and        65.4 μL of a 100 mg/mL dextran solution in water was added.        Three catheters each were top-coated with 28 μL of the        formulation.    -   3. Amorphous paclitaxel was obtained according to the procedure        described in example 8, starting with 8 mg paclitaxel. To the        paclitaxel residue 80 μL PEI of a 20 mg/mL PEI 750 kDa in water        solution and 80 μL of a 100 mg/mL Dextran solution in water was        added. Three catheters were top-coated with 15.8 μL of the        formulation.

The topcoats were dried under hot air and left further to dry over nightat room temperature. The balloons were then folded, pleated and sheathedin a nylon sheath. The balloons were subsequently placed in a 55° C.oven for 1 hour.

The full length catheters were tested according to the procedure inexample 12.

Release of the paclitaxel from the coating on the stubs was assessedaccording to the procedure as described in example 2.

Example 18A Topcoat Balloon with Oleylamine

Eight balloon stubs of 15 mm length were coated with the hydrophilicbase coat (R) as described in Example 1. The following formulations wereapplied on top of the basecoat.

-   -   1. 49.5 mg Jar-milled pacltitaxel was suspended in 495 μL        distilled water, vortexed and sonicated twice with sonic probe        for 20 seconds. Then 495 μL PEI 750 kDa at 20 mg/mL, pH        neutralized to 7 with 6N HCl, was added. Two stubs were        topcoated with 10 μL of the formulation per stub.    -   2. Paclitaxel was dissolved in methanol at 100 mg/mL. To 50 μL        of the paclitaxel solution, 50 μL of a 25 mg/mL PEI 750 kDa        solution in ethanol was added. Two stubs were topcoated with 10        μL of the formulation per stub.

3. Oleylamine was dissolved in ethanol at 20 mg/mL. 25 μL was added to75 μL of the 100 mg/mL paclitaxel solution in methanol. Two stubs weretopcoated with 7 μL of the formulation per stub.

The topcoats were dried under hot air and left further to dry over nightat room temperature. The balloons were then folded, pleated and sheathedin a nylon sheath. The balloons were subsequently placed in a 55° C.oven for 1 hour.

Release of the paclitaxel from the coating was then assessed accordingto the procedure as described in example 2.

Example 18B Topcoat Balloon with Polyurethanediol,Tricaprylylmethylammonium Chloride, Trimethylolpropane Ethoxylate,Pentaerythritol Ethoxylate and Jeffamine ED-900

Ten balloon stubs of 15 mm length were coated with the hydrophilic basecoat (R) and top-coated as described in Example 1. The followingformulations were applied on top of the basecoat. 100 mg Jar-milledpaclitaxel was suspended in 1 mL distilled water and thoroughlydispersed using vortex and sonic probe.

-   -   1. Polyurethanediol 88 wt. % was dissolved in water at 25 mg/mL.        55.7 mg of the paclitaxel suspension was weighed out and 40.7 μL        of the polyurethanediol solution was added. Two stubs were top        coated with 12.6 μt of the formulation per stub.    -   2. Tricaprylylmethylammonium chloride was dissolved in ethanol        at 25 mg/mL. 77.4 mg of the paclitaxel suspension was weighed        out and 56 μL of the Tricaprylylmethylammonium solution was        added. One stub was top coated with 12.6 μL of the formulation.    -   3. Trimethylolpropane ethoxylate 20/3 EO/OH was dispersed in        water at 25 mg/mL. 57.4 mg of the paclitaxel suspension was        weighed out and 41.7 μL of the trimathylolpropane ethoxylate        solution was added. Two stubs were top coated with 12.6 μL of        the formulation per stub.    -   4. Pentaerythritol ethoxylate 15/4 EO/OH was dissolved in water        at 25 mg/mL. 67.9 mg of the paclitaxel suspension was weighed        out and 49.4 μL of the Pentaerythritol ethoxylate solution was        added. Two stubs were topcoated with 12.6 μL of the formulation        per stub.    -   5. Jeffamine ED-900 was dissolved in water at 25 mg/mL. 59.8 mg        of the paclitaxel suspension was weighed out and 43.5 μL of the        Jeffamine solution was added. Two stubs were top coated with        12.6 μL of the formulation per stub.

The balloons were folded, pleated and sheathed in a nylon sheath. Theballoons were subsequently placed in a 55° C. oven for 1 hour.

Release of the paclitaxel from the coating was then assessed accordingto the procedure as described in example 2.

Example 19 Synthesized Linear and Branched PEI

The following compounds were synthesized based on dodecane-epoxylationof spermine, triethylamine glycol, 1-methyl-propyldiamine or other aminederivatives

Balloon stubs (22) were coated with the hydrophilic base coat (R) andreceived a topcoat as described in Example 1.

Preparation of formulations for the topcoats: Jar-milled paclitaxel wassuspended in water at 100 mg/mL and thoroughly dispersed using vortexand two times probe-sonication for 20 seconds at setting “2.5”. All ofthe following formulations were prepared by weighing out paclitaxelsuspension and adding a solution of an additive such that the w/w ratioof paclitaxel versus additive was 83:17% w/w. The resulting mixtureswere vortexed thoroughly and placed in a sonic bath for 10 minutes priorto applying the coating. Formulations (12.6 μL) were applied on top ofthe basecoat of each of 2 stubs and one metal coupon per formulation.The procedures for coating the stubs as described in example 1 werefollowed. The coatings on the metal coupons were weighed after thecoating was completely dry.

TABLE 4 Variable Values for Example 19. Paclitaxel Coat- suspen- Conc.Solvent Added ing sion (mg/ of Amount water weight Nr. (mg) Additive mL)additive (μL) (μL) (μg) 1 41 Trolamine 20 water 37.3 N/A 683 2 45.7Compound C 25 ethanol 33.2 83 777 3 41.1 Compound D 25 ethanol 29.9 7.5647 4 40.3 Compound E 25 ethanol 29.3 7.3 778 5 41.1 Linear PEI 20 warm37.4 N/A 692 2.5 kDa water 6 38.7 Linear PEI 20 warm 35.2 N/A 656 25 kDawater 7 45.3 Linear PEI 20 warm 41.2 N/A 717 250 kDa water 8 38.9Branched PEI 20 water 35.4 N/A 822 1.2 kDa 9 44.7 Branched PEI 20 water40.6 N/A 774 10 kDa 10 52.0 Branched PEI 20 water 47.3 N/A 795 50-100kDa Numbers 5-10 in Table 4 (PEI polymers) were purchased fromPolysciences, Inc.

The coated balloon stubs were dried under hot air and left further todry over night at room temperature. The balloons were folded, pleatedand sheathed in a nylon sheath. The balloons were subsequently placed ina 55° C. oven for 1 hour.

Release of the paclitaxel from the coating was then assessed accordingto the following procedure. Excised pig coronary arteries (Pel-FreezBiologicals) were prepared, placed in a plastic tube and kept at 37° C.Upon removal of the sheaths from the balloon stubs, the stubs were fixedto a motor and turned at a speed 125 rpm and immersed in Fetal BovineSerum (FBS) at 37° C. for 30 seconds. The balloons were removed from theFBS (methanol was then added to the FBS at a 1:3 FBS/methanol ratio byvolume in order to dissolve the paclitaxel). Next, the balloon wasexpanded in the artery tissue at 60-80 psi for 30 seconds while immersedin regular PBS at 37° C. and after deflation and removal of the balloon,the artery tissue was removed from the plastic tube and rinsed with PBSat 37° C. After removal of the balloon from the tissue and rinsing ofthe tissue, was placed in a methanol/0.1% acetic acid solution. Theresulting methanol and acetic acid solution was tested for paclitaxelcontent using HPLC (“Drug Transfer to Tissue”). The balloon was alsoplaced in methanol and 0.1% acetic acid solution.

Example 20 Crystalline (Jar Milled Vs Sonicated) Vs Amorphous Paclitaxel

Balloon stubs (22) were coated with the hydrophilic base coat (R) andreceived a paclitaxel containing topcoat as described in Example 1. Thefollowing formulations were coated on balloon-stubs with hydrophilicbase-coat R (n=2 per formulation).

-   -   a) Paclitaxel (75 mg) was dissolved in 750 μL methanol.        Paclitaxel solution (75 μL) was mixed with 25 μL of a PEI 750        kDa solution at 25 mg/mL in ethanol. 8.8 μL of the resulting        solution was applied as top-coat on two stubs.    -   b) Jar-milled paclitaxel was suspended in water at 100 mg/mL and        thoroughly dispersed using vortex and two times probe-sonication        for 20 seconds at setting “2.5”. All of the following        formulations were prepared by weighing out paclitaxel suspension        and adding a solution of an additive such that the w/w ratio of        paclitaxel versus additive was 83:17% w/w. The resulting        mixtures were vortexed thoroughly and placed in a sonic bath for        10 minutes prior to applying the coating. 13.9 μL of the        resulting solution was applied as top-coat on two stubs.

TABLE 5 Variable Values for Example 20. Paclitaxel suspen- Conc. SolventAdded sion (mg/ of Amount water Nr. (mg) Additive mL) additive (μL) (μL)84.8 PEI 750 kDa 20 Water (add 77.0 N/A HCl to pH 7.0) 90.6 Tricaprylyl25 ethanol 65.8 16.5 methylamine 91.5 Spermine 20 water 83.2 N/A 90.4Compound A 25 ethanol 65.7 16.5 95.3 Compound B 25 ethanol 69.3 17.390.3 Compound F 25 ethanol 65.7 16.4 96.7 Compound G 25 ethanol 70.317.6 86.5 Compound H 25 ethanol 62.9 15.7 91.8 L-ornithine 20 water 83.4N/A 88.9 Choline•HCl 20 water 80.8 N/A

The coated balloon stubs were dried under hot air and left further todry over night at room temperature. The balloons were folded, pleatedand sheathed in a nylon sheath. The balloons were subsequently placed ina 55° C. oven for 1 hour.

Release of the paclitaxel from the coating was then assessed accordingto the following procedure. Excised pig coronary arteries (availablefrom Pel-Freez Biologicals) were prepared, placed in a plastic tube andkept at 37° C. Upon removal of the sheaths from the balloon stubs, thestubs were fixed to a motor and turned at a speed 125 rpm and immersedin Horse Serum (HS) at 37° C. for 30 seconds. The balloons were removedfrom the HS. Next, the balloon was expanded in the artery tissue at60-80 psi for 30 seconds while immersed in regular PBS at 37° C. andafter deflation and removal of the balloon, the artery tissue wasremoved from the plastic tube and rinsed with PBS at 37° C. Afterremoval of the balloon from the tissue and rinsing of the tissue, wasplaced in a methanol/0.1% acetic acid solution. The resulting methanoland acetic acid solution was tested for paclitaxel content using HPLC(“Drug Transfer to Tissue”). The balloon was also placed in methanol and0.1% acetic acid solution.

Example 21 PEI, L-citruline, Poly-L-ornithine and Poly-L-glutamic Acid

Nine balloon stubs were coated with the hydrophilic base coat (R) andreceived a top-coat as described in Example 1.

Preparations for the topcoats: Jar-milled paclitaxel was suspended inwater at 100 mg/mL and thoroughly dispersed using vortex and two timesprobe-sonication for 20 seconds at setting “2.5”. All of the followingformulations were prepared by weighing out 50 mg of the paclitaxelsuspension and adding 45.5 μL of a 20 mg/mL of an aqueous solution ofthe additives such that the w/w ratio of paclitaxel versus additives was83:17 w/w. The resulting mixtures were vortexed thoroughly and placed ina sonic bath for 10 minutes prior to applying the coating. The followingadditives were used:

(1) PEI 750 kDa; added HCl to pH 7.0

(2) L-citruline

(3) poly-L-ornithine

(4) poly-L-glutamic acid

The resulting formulation (13.9 μL) was applied as a topcoat on stubs(n=3 for PEI, n=2 per formulation for other additives).

The coated stubs were dried under hot air and left further to dry overnight at room temperature. The balloons were folded, pleated andsheathed in a nylon sheath. The balloons were subsequently placed in a55° C. oven for 1 hour.

Release of the paclitaxel from the coating was assessed according to theprocedure described in example 20.

Example 22 Branched PEI with Oleic Acid Grafts and Amino Acid MethylEsters

Eight balloon stubs were coated with the hydrophilic base coat (R) andreceived a top-coat as described in Example 1. Jar-milled paclitaxel wassuspended in water at 100 mg/mL and thoroughly dispersed using vortexand two times probe-sonication for 20 seconds at setting “2.5”. All ofthe following formulations were prepared by weighing out paclitaxelsuspension and adding a solution of an additive such that the w/w ratioof paclitaxel versus additive was 83:17% w/w.

TABLE 6 Variable Values for Example 22. Paclitaxel suspension Conc.Solvent of Amount Nr. (mg) Additive (mg/mL) additive (μL) 1 92.7spermine-oleate 20 ethanol 84.3 (ethanol) 2 90.7 PEI(10 kDa)-oleate 20ethanol 82.4 2:1 (ethanol 3 89.0 PEI 750 kDa-oleate 20 water 80.9 1:1(ethanol) 4 95.4 PEI(1200 Da)-oleate 20 ethanol 86.7 2:1 (water)

The resulting mixtures were vortexed thoroughly and placed in a sonicbath for 10 minutes prior to applying the coating. The resultingsolution (13.8 μL) was applied as top-coat on each of two stubs. Thecoated stubs were dried under hot air and left further to dry over nightat room temperature. The balloons were folded, pleated and sheathed in anylon sheath. The balloons were subsequently placed in a 55° C. oven for1 hour.

Release of the paclitaxel from the coating was assessed according to theprocedure described in example 20.

Example 23 PAMAM Derivatives

In this study various different PAMAMs were investigated with eitheracid (COOH) end groups or similar generation-4 amine end groups withdifferent building blocks.

The chemical formula of PAMAM 4^(th) gen—polyamidoamine dendrimer, basedon an ethylenediamine core is as follows:

Fifteen balloon stubs were coated with the hydrophilic base coat (R) asdescribed in Example 1.

Preparations for the Topcoats:

Approximately 10 mg sonicated paclitaxel (see experiment 1) was weighedout and suspended in water at 100 mg/mL. A solution of a PAMAM was addedto the paclitaxel suspension such that the w/w ratio of paclitaxelversus additives was 83:17% w/w. The resulting mixtures were vortexedthoroughly and two times probe-sonication for 20 seconds at setting“2.5” and placed in a sonic bath for 10 minutes prior to use forapplying the top-coat (applied according to procedure in Example 1).Three stubs were coated per formulation.

TABLE 7 Variable Values for Example 23 Conc. Solvent Added (mg/ ofAmount methanol Num. PAMAM CAS No. mL) additive (μL) (μL) 1 Gen 4163442- 100 methanol 20 N/A 67-9 2 Gen 1.5 202009- 200 methanol 10 1064-1 3 Gen 3.5 192948- 100 methanol 20 N/A 77-9 4 Gen 4 (Dab- 120239-100 methanol 10 N/A Am-4) 63-6 5 Gen 4 (hexyl) Not 100 methanol 10 N/Aassigned; Sigma Cat. No.: 640921

The topcoats were dried under hot air and left further to dry over nightat room temperature. The balloons were folded, pleated and sheathed in anylon sheath. The balloons were subsequently placed in a 55° C. oven for1 hour.

Release of the paclitaxel from the coating was assessed according to theprocedure described in example 20.

Example 24 PAMAM with Different Molecular Weights

PAMAM is a polyamidoamine dendrimer (i.e. contains both amide and aminegroups; see exemplary chemical structure below).

PAMAM is a globulin polymer and synthesized in generations: everyfollowing generation, as the molecular weight increased it isaccompanied by an exponential increase in number of branches. In thisexample a series of generations was tested at both 90:10 and 75:25PTX/PAMAM.

Twenty eight balloon stubs were coated with the hydrophilic base coat(R) and received a top-coat as described in Example 1.

Preparations for the Topcoats:

PAMAM solutions of generation 0, 1, 2, 3, 4, 5 and 7 with ethylenediamine core were obtained (available from Sigma) and diluted inmethanol to 50 mg/mL. Sonicated paclitaxel (see experiment 1) wassuspended in water at 50 mg/mL and thoroughly dispersed using vortex andtwo times probe-sonication for 20 seconds at setting “2.5”.

TABLE 8 CAS Nos. for PAMAM Derivatives. PAMAM Gen CAS No. 0 155773-72-11 142986-44-5 2  93376-66-0 3 153891-46-4 4 163442-67-9 5 163442-68-0 7163442-70-4

A. Paclitaxel/PAMAM formulations at 90:10 w/w ratio.

-   -   Paclitaxel (50 mg) suspension was weighed out and 5.3 μL of a        PAMAM solution at 50 mg/mL in methanol was added. The        formulations were placed in a sonic bath for 10 minutes before        it was used to apply the top-coat. Two stubs were coated per        formulation.

B. Paclitaxel/PAMAM formulations at 75:25 w/w ratio.

-   -   Paclitaxel suspension (50 mg) was weighed out and 15.9 μL of a        PAMAM solution at 50 mg/mL in methanol was added. The        formulations were placed in a sonic bath for 10 minutes before        it was used to apply the top-coat. Two stubs each were coated        per formulation.

The topcoats were dried under hot air and left further to dry over nightat room temperature. The balloons were folded, pleated and sheathed in anylon sheath. The balloons were subsequently placed in a 55° C. oven for1 hour. Release of the paclitaxel from the coating was assessedaccording to the procedure described in example 20.

TABLE 9 Tissue Transfer (μg) and Standard Deviations for Examples 16-23.Active Agent Tissue transfer Standard Example Description (μg) DeviationExample 16 PEI-HMW/PTX 8:92 w/w in 254.68 34.51 methanol (1, 2)PAMAM/PTX 8:92 w/w in 259.80 35.47 methanol (3, 4) PEI-HMW/PTX(amorphous) 14.25 3.81 17:83 w/w (5, 6, 7) PEI-HMW/PTX (jar milled)17:83 149.36 19.94 w/w (8, 9, 10) PAMAM/PTX (jar milled) 17:83 189.460.76 w/w (11, 12) Example 17 83% PTX (jar milled)/17% PEI- 120.98 14.86HMw w/w 45.5% PTX (jar milled)/9% PEI- 27.53 1.84 HMw/45.5% dextran w/w45.5% PTX (amorphous)/9% PEI- 115.83 34.10 HMw/45.5% dextran Example 18APEI/PTX 20:80 w/w in methanol 240.53 71.69 Oleylamine/PTX 8:92 w/w in96.60 33.94 methanol PEI/PTX (sonicated) 17:83 w/w 76.66 17.68 pH 7.0Example 18B Polyurethanediol 42.84 21.72 Tricaprylylmethylammonium327.84 Chloride Trimethylolpropane ethoxylate 88.42 40.25Pentaerythritol ethoxylate 20.06 7.27 Jeffamine ED-900 37.52 5.88Example 19 Trolamine 21.58 5.52 Compound C 127.06 13.55 Compound D 96.7425.54 Compound E 59.72 15.27 Linear PEI 2.5 kDa 96.46 74.25 Linear PEI25 kDa 43.88 14.20 Linear PEI 250 kDa 42.66 4.95 Branched PEI 1.2 kDa55.00 13.97 Branched PEI 10 kDa 127.70 37.87 Branched PEI 50-100 kDa177.82 41.95 Example 20 PTX/PEI 750 kDa 92:8 w/w in 27.90 2.86 methanolPTX/PEI 750 kDa 83:17 w/w jar 145.44 1.53 milled Tricaprylyl methylamine123.32 56.57 Spermine 38.10 9.87 Compound A 84.64 10.86 Compound B 47.9411.34 Compound F 44.28 8.09 Compound G 25.60 23.14 Compound H 32.66 2.57L-ornithine 52.82 1.10 Choline•HCl 36.28 11.99 Example 21 PEI 750 kDa,pH 7.0 179.8 62.83 L-citruline 56.62 9.02 poly-L-ornithine 113.4 21.10poly-L-glutamic acid 34.3 6.76 Example 22 spermine-oleate (ethanol)84.08 10.74802 PEI(10 kDa)-oleate 2:1 (ethanol 41.94 1.612203 PEI 750kDa-oleate 1:1 (ethanol) 28.62 12.13395 PEI(1200 Da)-oleate 2:1 (water)63.28 9.842926 Example 23 PAMAM Gen 4 (163442-67-9) 100.89 35.93021PAMAM Gen 1.5 (202009-64-1) 31.68 11.23829 PAMAM Gen 3.5 (192948-77-9)43.24 3.178931 PAMAM Gen 4 (Dab-Am-4; 15.88 8.566633 (120239-63-6) PAMAMGen 4 (hexyl; Sigma cat. 30.68 20.23051 No.: 640921) Example 24 10:90PAMAM:PTX; w/w PAMAM gen 0 47.32 18.83732 PAMAM gen 1 57.6 16.06547PAMAM gen 2 103.22 47.60243 PAMAM gen 3 82.56 PAMAM gen 4 176.2610.15405 PAMAM gen 5 129.24 42.36984 PAMAM gen 7 123.72 17.02713 25:75PAMAM:PTX w/w PAMAM gen 0 41.54 2.008183 PAMAM gen 1 26.7 3.196123 PAMAMgen 2 58.72 4.186072 PAMAM gen 3 124.88 PAMAM gen 4 107.86 5.854844PAMAM gen 5 92.78 8.513566 PAMAM gen 7 105.92 49.78032

It should be noted that, as used in this specification and the appendedclaims, the singular forms “a,” “an,” and “the” include plural referentsunless the content clearly dictates otherwise. Thus, for example,reference to a composition containing “a compound” includes a mixture oftwo or more compounds. It should also be noted that the term “or” isgenerally employed in its sense including “and/or” unless the contentclearly dictates otherwise.

It should also be noted that, as used in this specification and theappended claims, the phrase “configured” describes a system, apparatus,or other structure that is constructed or configured to perform aparticular task or adopt a particular configuration to. The phrase“configured” can be used interchangeably with other similar phrases suchas arranged and configured, constructed and arranged, constructed,manufactured and arranged, and the like.

All publications and patent applications in this specification areindicative of the level of ordinary skill in the art to which thisinvention pertains. All publications and patent applications are hereinincorporated by reference to the same extent as if each individualpublication or patent application was specifically and individuallyindicated by reference. To the extent inconsistencies arise betweenpublications and patent applications incorporated by reference and thepresent disclosure, information in the present disclosure will govern.

The invention has been described with reference to various specific andpreferred embodiments and techniques. However, it should be understoodthat many variations and modifications may be made while remainingwithin the spirit and scope of the invention.

1. A drug delivery device comprising: a substrate; a hydrophilic polymerlayer disposed on the substrate; and coated therapeutic agent particlesdisposed on the hydrophilic polymer layer, the coated therapeutic agentparticles comprising a particulate hydrophobic therapeutic agent, theparticulate hydrophobic therapeutic agent having an average diameter ofbetween 100 nm and 10 μm; and a cationic agent in contact with theparticulate hydrophobic therapeutic agent.
 2. The drug delivery deviceof claim 1, the particulate hydrophobic therapeutic agent having anaverage diameter of between 0.3 μm to about 1 μm.
 3. The drug deliverydevice of claim 1, the cationic agent having a molecular weight ofbetween 2.5 kDa and 2,000 kDa.
 4. The drug delivery device of claim 1,the cationic agent having a molecular weight of between 50 kDa and 100kDa.
 5. The drug delivery device of claim 1, further comprising anadditive disposed between the coated therapeutic agent particles, theadditive selected from the group consisting of saccharides andamphiphilic compounds
 6. The drug delivery device of claim 5, theadditive selected from the group consisting of glycogen, dextran, andnon-ionic co-polymer of ethylene and propylene oxide.
 7. The drugdelivery device of claim 1, further comprising an additive disposedbetween the coated therapeutic agent particles, the additive selectedfrom the group consisting of polyethylene glycol and derivativesthereof, polyvinyl pyrrolidone and derivatives thereof, polyvinylalcohol and derivatives thereof, polyoxazolines, and poloxamers.
 8. Thedrug delivery device of claim 1, the coated therapeutic agent particlesexhibiting a Zeta potential of greater than +10 mV.
 9. The drug deliverydevice of claim 1, further comprising nucleic acids associated with thecationic agent.
 10. The drug delivery device of claim 1, the hydrophobicparticulate therapeutic agent having a solubility in water at 25 degreesCelsius of less than 100 μg/mL.
 11. The drug delivery device of claim 1,the cationic agent exhibiting affinity for the surface of a cellmembrane.
 12. The drug delivery device of claim 1, the cationic agentselected from the group consisting of cationic lipids, cationicpolymers, and lipidoids.
 13. The drug delivery device of claim 1, thecationic agent comprising PEI.
 14. The drug delivery device of claim 1,the cationic agent comprising DOTAP or PAMAM.
 15. The drug deliverydevice of claim 1, the particulate hydrophobic therapeutic agentselected from the group consisting of paclitaxel, sirolimus,zotarolimus, everolimus, temsirolimus, pimecrolimus, tacrolimus,ridaforolimus and analogs thereof.
 16. The drug delivery device of claim1, the hydrophilic polymer layer comprising polyacrylamide.
 17. The drugdelivery device of claim 1, the hydrophilic polymer layer comprisingpolyvinylpyrrolidone.
 18. The drug delivery device of claim 1, thehydrophilic polymer layer covalently bonded to the substrate.
 19. Thedrug delivery device of claim 1, the hydrophilic polymer layercross-linked with a photoactivatable cross-linking agent.
 20. The drugdelivery device of claim 1, the device comprising a drug-containingballoon catheter.
 21. A drug delivery coating comprising a polymericlayer, the polymeric layer comprising a hydrophilic surface; coatedtherapeutic agent particles disposed on the hydrophilic surface, thecoated therapeutic agent particles comprising a particulate hydrophobictherapeutic agent core, the particulate hydrophobic therapeutic agentcore having an average diameter of between 100 nm and 10 μm; and acationic agent in contact with the particulate hydrophobic therapeuticagent core.
 22. The drug delivery coating of claim 21, the particulatehydrophobic therapeutic agent having an average diameter of between 0.3μm to about 1 μm.
 23. The drug delivery coating of claim 21, thecationic agent having a molecular weight of between 2.5 kDa and 2,000kDa.
 24. The drug delivery coating of claim 21, the cationic agenthaving a molecular weight of between 50 kDa and 100 kDa.